# Nationalization of the county vote: report

Chapter 10.1 of The Public Mind, by Vishal Singh (NYU Stern). Generated from the chapter's data files; the reading version is at https://vishalsingh.org/politics/nationalization-of-the-county-vote. Table n of this report is figure n of the chapter.

## Identification

- Title: Nationalization of the county vote
- Chapter: 10.1 (Part X, The nationalized map; The political map)
- Question: How uniform are county swings in presidential elections, and how has that changed since 1868?
- Dek: Counties moved more nearly in step in 2020 to 2024 than in any other pair of presidential elections since 1868, with a vote-weighted standard deviation of county swings of 4.5 points against 5.0 in 2008 to 2012, the next lowest.
- Grain: places
- Status: draft
- Published: 2026-09-30
- Updated: not revised
- Data sources:
  - County election returns. County presidential returns, 1868-2024: Algara and Amlani (1868-2020) and MIT Election Data and Science Lab (2024), repaired file; years: President 1868-2024 (40 elections); House and Senate 1990-2024; weights: none (full counts); county swings weighted by two-party votes in the later election, county-equal in one view
- Canonical URL: https://vishalsingh.org/politics/nationalization-of-the-county-vote
- Report: https://vishalsingh.org/politics/nationalization-of-the-county-vote/report
- Markdown: https://vishalsingh.org/politics/nationalization-of-the-county-vote/report.md
- BibTeX key: singh2026nationalizationofthecountyvote

```bibtex
@misc{singh2026nationalizationofthecountyvote,
  author = {Singh, Vishal},
  title = {Nationalization of the county vote},
  year = {2026},
  url = {https://vishalsingh.org/politics/nationalization-of-the-county-vote},
  note = {In The Public Mind. Published 30 September 2026.}
}
```

## Principal estimates

The facts the dek and the opening prose cite, in order of appearance.

| Estimand | Population | Period | Value | Interval | n | Weights | Source | Fact id |
| --- | --- | --- | ---: | --- | ---: | --- | --- | --- |
| vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 | 4.5 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns | sd_w_latest |
| vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 | 5.0 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns | sd_w_2012 |
| threshold on the vote-weighted standard deviation | threshold for counting pairs | 1868-2024 | 10 |   |   | none (full counts) | County election returns | cut |
| count of pairs with a vote-weighted standard deviation above the threshold | pairs ending in 1984 or earlier | 1868 to 1984 | 28 |   |   | none (full counts) | County election returns | n_early_above |
| count of pairs | pairs ending in 1984 or earlier | 1868 to 1984 | 29 |   |   | none (full counts) | County election returns | n_early |
| count of pairs with a vote-weighted standard deviation below the threshold | pairs ending in 1988 or later | 1984 to 2024 | 9 |   |   | none (full counts) | County election returns | n_late_below |
| count of pairs | pairs ending in 1988 or later | 1984 to 2024 | 10 |   |   | none (full counts) | County election returns | n_late |
| count of counties matched on FIPS | counties with returns in both elections of the pair, Alaska excluded | 1868 to 1872 | 1,687 |   |   | none (full counts) | County election returns | n_matched_first |
| count of counties matched on FIPS | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 | 3,111 |   |   | none (full counts) | County election returns | n_matched_latest |
| share of two-party votes cast in matched counties | counties with returns in both elections of the pair, Alaska excluded | 1868 to 1872 | 91.7% |   |   | none (full counts) | County election returns | cov_first |
| lowest share of two-party votes cast in matched counties, pairs after 1868 to 1872 | counties with returns in both elections of the pair, Alaska excluded | 1872 to 2024 | 97.7% |   |   | none (full counts) | County election returns | cov_min |

## Findings

Counties moved more nearly in step in 2020 to 2024 than in any other pair of consecutive presidential elections since 1868. The spread of county swings, measured by its vote-weighted standard deviation, was 4.5 points in 2020 to 2024. It was above 10 points in 28 of the 29 pairs of consecutive elections through 1980 to 1984 and below 10 points in 9 of the 10 pairs from 1984 to 1988 on. The lead of 2020 to 2024 over 2008 to 2012, the next lowest pair, is small, and the last section checks that it holds under other measures.

A county's swing is the change in its two-party margin from one presidential election to the next, in points of margin, and a positive swing is a move toward the Democrats. The national swing is the same change in the summed margin of the matched counties, the ones that reported in both elections. A county's relative swing is its swing minus the national swing, which is zero for a county that moved exactly with the country. If every county did, the spread of relative swings would be zero too. Political scientists call the loss of local variation in electoral change nationalization, and the spread of swings is this chapter's measure of it. That measure differs from the one that Amlani and Algara [1] apply to the same county returns for 1872 to 2020. (Note: Counties are weighted by their two-party votes in the later election unless a figure says otherwise, so a large county counts for more than a small one. Each pair of elections uses the counties that reported in both, matched on FIPS code, which gives 1,687 counties in 1868 to 1872 and 3,111 in 2020 to 2024. Florida, Mississippi, Texas and Virginia have no county rows for 1868, and Colorado, admitted in 1876, first appears in 1880. The first pair therefore covers 91.7% of the two-party votes cast in 1872, mainly because of those gaps, and every later pair covers at least 97.7% of the two-party votes cast in its later election.)

The chapter keeps three readings of the returns apart. The spread of swings measures how far county swings disperse around their mean. The share of votes cast in counties close to the national swing measures distance from the national result, and the two readings differ when the mean county swing and the national swing differ. The correlation of county margins between consecutive elections measures how far differences in county levels persist from one election to the next.

### The spread of county swings narrowed after 1984

Table 1 plots the spread for every pair, at the later election. Through 1980 to 1984 only 1940 to 1944, at 6.4 points, was at or below 10 points. From 1984 to 1988 on only 2012 to 2016, at 10.8 points, was at or above it. The 9 later pairs below the cutoff ranged from 4.5 to 7.9 points, with the lowest value in 2020 to 2024 after 5.7 in 2016 to 2020. That value is 0.5 points below 2008 to 2012, the next lowest pair at 5.0. (Note: The counts of pairs above and below 10 points depend on the cutoff. At 8 points they are 28 of 29 and 9 of 10, and at 12 points they are 22 of 29 and 10 of 10.)

Table 1. The spread of county swings was above 10 points in 28 of 29 pairs through 1984 and below it in 9 of 10 since

Shaded columns mark pairs that are hard to compare with the rest. The two Reconstruction pairs come first. The others include an election in which candidates outside the two major parties won at least 10% of all votes, which happened in 1892, 1912, 1924, 1968, 1992 and 1996. The widest pair, 1892 to 1896, at 39.0 points, is one of them. The two-party margin leaves those votes out, and 7 of the ten largest spreads fall in shaded pairs.

The spread rose in 4 of the 10 pairs from 1984 to 1988 on, and the largest rise, 5.8 points, came in 2012 to 2016. That pair had the lowest share of votes within 5 points of the national swing, 34.0%, of any pair after 1980 to 1984. The correlation of county margins with the previous election's fell to 0.96 from 0.99. Both recovered in 2016 to 2020. The spread measures how unevenly counties moved in 2016 and not which kinds of counties moved; Chapter 12.7, Education, ethnicity and the county shift, 2016 to 2024 (https://vishalsingh.org/politics/education-ethnicity-and-the-county-shift) follows the county shift from that year to 2024.

Nationalization has a long literature. Stokes [2] distinguished national from sub-national electoral forces, and Bartels [3] estimated them from state-level presidential returns for 1868 to 1996 and found a system more nationalized than a century earlier. Claggett, Flanigan and Zingale [4] found no trend toward increasing nationalization of the vote from 1842 to 1970. Amlani and Algara [1] use the county file this chapter draws on, for presidential, Senate and gubernatorial elections from 1872 to 2020. They conclude that contemporary elections are highly nationalized and that presidential and Senate elections are more partisan than in any period since the Civil War. Caramani [5] traced the same process across Western European constituencies, and Hopkins [6] documents it in American attitudes and behavior with surveys and experiments. The spread of county swings does not reproduce the measures of these studies. How far counties sit from the national result in a single election, as against how far they moved, is the subject of Chapter 10.2, Distance from the national vote, 1868 to 2024 (https://vishalsingh.org/politics/the-landslide-county).

### Relative swings narrowed to a ridge near zero

Table 2 shows the distribution behind the spread for nine pairs, the ones ending in 1876, 1896, 1916, 1936, 1956, 1976, 1996 and 2016, and the latest pair. The earliest ridges are low and reach past the edges of the plot. In 1892 to 1896, 10.0% of votes were cast in counties whose relative swing lay more than 60 points from zero on one side or the other. The last ridge is narrow, and 73.1% of the votes in 2020 to 2024 fall within 5 points of zero, against 22.7% in 1892 to 1896 and 20.3% in 1972 to 1976. Its mass sits above zero. The vote-weighted median county swing was +1.8 points relative to the national swing. 19.8% of votes were cast in counties that swung 5 or more points more toward the Democrats than the nation, and 7.1% in counties that swung that far more toward the Republicans. The reference behind this offset is discussed with Table 4.

Table 2. Relative county swings lay far from zero in early pairs and sat in a narrow band just above zero in 2020 to 2024

### Counties near the national swing, 1868 to 2024

Table 3 shows the same relative swings county by county, for the pair of elections chosen with the slider. The palest class holds counties within 5 points of the national swing. In 2020 to 2024, 75.6% of matched counties fall in that class, the largest share of the 39 pairs. The smallest share, 8.5%, is in 1924 to 1928, a pair that includes a strong third-party vote, and 1972 to 1976 gives 21.2%. The national swing in the last pair was −6.1 points, a move toward the Republicans, so a blue county in that pair moved less toward the Republicans than the nation did, or toward the Democrats.

Table 3. The share of counties within 5 points of the national swing rose from 21.2% in 1972 to 1976 to 75.6% in 2020 to 2024

### Share of votes near the national swing

The share of votes cast in counties within 5 points of the national swing is a coarser summary than the spread, and it is easier to read. Table 4 plots it. The share was 73.3% in 2008 to 2012, fell to 34.0% in 2012 to 2016 and was 73.1% in 2020 to 2024. No pair through 1980 to 1984 exceeded 62.0%, the value for 1940 to 1944. The two records therefore fall in different pairs. The spread is lowest in 2020 to 2024, and the share of votes near the national swing is highest in 2008 to 2012. The spread gives large deviations more weight than the share does, which is why the two measures can rank neighboring pairs differently. Counted by county, the share was 75.6% in 2020 to 2024 and 58.8% in 2008 to 2012. It is higher than the vote share in 2020 to 2024 and lower in 2008 to 2012.

The reference matters when the spread is small. Measured against the vote-weighted mean of county swings instead of the national swing, 80.0% of votes and 86.3% of counties were within 5 points in 2020 to 2024, against 73.1% and 75.6% for the national swing. This chapter uses the national swing. (Note: The national swing is the change in the summed margin, so it reflects where votes were cast as well as how counties voted. The vote-weighted mean of county swings gives each county its later-election weight in both elections and leaves that change out. In 2020 to 2024 the first was −6.1 points and the second −4.8, a gap of −1.3.)

Table 4. The share of votes near the national swing was 73.3% in 2008 to 2012 and 73.1% in 2020 to 2024, the two highest of 39 pairs

### County swings in the South were wider until 1992

Table 5 splits the matched counties into the Census Bureau's South region and the rest and gives the spread inside each. Within the South the spread was larger than in the rest of the country in each of 13 consecutive pairs from 1940 to 1944 through 1988 to 1992. The run ends on small gaps. The South's spread exceeded the rest's by 1.6 points in 1984 to 1988 and 0.1 points in 1988 to 1992, and the rest of the country's was the larger by 1.7 points in 1992 to 1996. In 1960 to 1964 the spread was 33.5 points inside the South and 11.4 outside, and in 1972 to 1976 it was 20.7 and 9.7. The shaded pair of 1964 to 1968, which includes the 1968 third-party vote, was higher still inside the South, at 39.2 points. The shaded columns in Table 5 mark the same pairs as in Table 1. Before 1940 the pattern is mixed, and the rest of the country had the larger spread in 10 of the 18 pairs through 1936 to 1940.

Switching to South against the nation compares the South's own margin swing with the national swing. A negative value means the South moved further toward the Republicans than the nation did. The South's margin swing differed from the nation's by +21.9 points in 1972 to 1976. Since 1984 to 1988 the difference has stayed within 2.4 points, and in 2020 to 2024 the spread is 4.4 points in the South and 4.5 elsewhere.

Table 5. The spread of county swings was 33.5 points in the South and 11.4 elsewhere in 1960 to 1964, and 4.4 and 4.5 in 2020 to 2024

### County margins and winners track the last election more closely

A second view of nationalization asks how far differences in county levels persist, measured by how well a county's margin in one election predicts its margin in the next. Table 6 plots the vote-weighted correlation between county margins in each pair, and between margins four elections apart. The correlation with the previous election was 0.33 in 1892 to 1896, 0.51 in 1960 to 1964 and 0.51 in 1972 to 1976. It was above 0.9 in 3 of the 29 pairs through 1980 to 1984 and in all 10 pairs from 1984 to 1988 on. It is 0.99 in each of 2008 to 2012, 2016 to 2020 and 2020 to 2024, and 0.96 in 2012 to 2016. Across four elections the correlation was 0.85 between 1972 and 1988 and is 0.90 between 2008 and 2024.

The correlation depends on how spread out county margins are as well as on the spread of swings, so it accompanies the spread measure and does not replace it.

Table 6. County margins correlated with the previous election's margins above 0.9 in 3 of 29 pairs through 1984 and in all 10 pairs since

County winners persisted in the same way. Applying the national swing to every county gives a test. A county's predicted margin is its margin in the earlier election plus the national swing, and its winner is called from the sign. Keeping each county's earlier winner instead gets 50.9% of counties wrong in 1972 to 1976, 1,584 counties, and 2.8% in 2020 to 2024, 87 counties. The national swing cuts the number of counties called wrong by 26% in 1972 to 1976 and 28% in 2020 to 2024, to 37.8% and 2.0% of counties. The fall in the error rate therefore follows the fall in the number of counties that changed winner and does not reflect a better fit of the uniform swing. The national swing comes from the later election's own results, so the test is a fit and not a forecast. The count depends on how many counties sit close to an even split as well as on how far they swing.

### The 2020 to 2024 low holds under other measures

The lead of 2020 to 2024 over 2008 to 2012 is small, so this section asks whether it depends on the measure or on the counties included. Leaving out any one state or the District of Columbia in turn keeps 2020 to 2024 the lowest pair, with a gap to 2008 to 2012 of 0.3 to 0.7 points.

The Votes and counties view of Table 1 adds a line that counts each county once. That gives a larger spread in 35 of the 39 pairs, so the small counties, which count for less in the vote-weighted figure, usually have the more varied swings. The vote-weighted spread is the larger one in 1932 to 1936, 2012 to 2016, 2016 to 2020 and 2020 to 2024. In 2020 to 2024 it is 4.5 points against 3.4 for the county-equal version, so votes are concentrated in counties whose swings sit further from the mean than the typical county's do. The county-equal lead is wider, 3.4 points in 2020 to 2024 against 5.2 in 2016 to 2020, the next lowest, a gap of 1.8 points.

The main measure could also depend on how small counties, the changing county set or extreme counties are handled. There are five measures, each computed with vote weights and with each county counted once, which gives 10 versions, and 2020 to 2024 is the lowest pair in every one (Table 7). The measures are the standard deviation, the standard deviation after dropping counties with fewer than 1,000 two-party votes in either election, the standard deviation on the fixed panel of 1,652 counties with votes in all 40 elections, and two that give little weight to extreme counties, the median absolute deviation and the interquartile range. (Note: The median absolute deviation is the middle value of the distances of county swings from their median, and the interquartile range is the distance between the swings at the 25th and 75th percentiles. Each is scaled to equal the standard deviation for a normal distribution.)

Table 7. 2020 to 2024 is the lowest pair under all 10 versions of the spread

### What these data cannot show

County returns describe places, not voters. A county that swings with the nation can contain groups that moved in opposite directions, and returns cannot separate voters who changed their choice from people who started or stopped voting or moved in or out, a limit known as ecological inference. The national swing has a related limit. It is a change in a summed margin, so it counts where votes were cast as well as how counties voted, and in 2020 to 2024 it differed from the mean county swing by −1.3 points.

The returns are full counts, so the figures carry no sampling intervals, and differences between measures come from how they are defined and which counties enter. The county set is one of those choices. Counties are matched on FIPS code and boundaries are not harmonized, so a county that gained or lost territory is treated as one unit, and the county-equal figures depend on how many small counties exist. The 53 county rows that have Democratic and Republican votes but no total vote count are left out, among them 27 Idaho counties in 1912, and keeping them changes no pair's spread by more than 0.12 points. Returns before 1965 count the votes of the people allowed to vote. In much of the South, barriers to voting kept many Black citizens from the ballot until the Voting Rights Act, so early margins describe smaller electorates than the populations of those counties. The two-party margin also leaves out third-party votes, which is why the shaded pairs in Table 1 are the least comparable with the rest.

The chapter measures how uniformly counties moved and does not say why. How much of the county vote census characteristics account for is the subject of Chapter 12.1, Five axes of the county vote (https://vishalsingh.org/politics/five-axes-of-the-county-vote), and ticket splitting is taken up in Chapter 10.3, Down the ballot (https://vishalsingh.org/politics/down-the-ballot). Chapter 10.4, The Electoral College (https://vishalsingh.org/politics/the-electoral-college; planned) turns state margins into electoral outcomes, and Chapter 15.1, Party and place (https://vishalsingh.org/politics/party-and-place) compares how far partisans' issue positions differ between deep-red and deep-blue counties with the gap between the parties. The series also makes no forecast. The spread was 5.0 points in 2008 to 2012 and 10.8 in 2012 to 2016.

## Tables

### Table 1. The spread of county swings was above 10 points in 28 of 29 pairs through 1984 and below it in 9 of 10 since

Standard deviation of county swings in the two-party margin, percentage points; one point per pair of consecutive presidential elections, plotted at the later election

| View | Pair of elections | Measure | Spread (points) | Counties |
| --- | --- | --- | ---: | ---: |
| weighted | 1868–72 | Vote-weighted | 31.88 | 1,687 |
| weighted | 1872–76 | Vote-weighted | 29.11 | 2,151 |
| weighted | 1876–80 | Vote-weighted | 12.83 | 2,216 |
| weighted | 1880–84 | Vote-weighted | 11.84 | 2,283 |
| weighted | 1884–88 | Vote-weighted | 10.25 | 2,345 |
| weighted | 1888–92 | Vote-weighted | 17.31 | 2,424 |
| weighted | 1892–96 | Vote-weighted | 39.03 | 2,654 |
| weighted | 1896–1900 | Vote-weighted | 22.85 | 2,695 |
| weighted | 1900–04 | Vote-weighted | 16.53 | 2,680 |
| weighted | 1904–08 | Vote-weighted | 14.91 | 2,707 |
| weighted | 1908–12 | Vote-weighted | 23.94 | 2,832 |
| weighted | 1912–16 | Vote-weighted | 26.08 | 2,942 |
| weighted | 1916–20 | Vote-weighted | 17.04 | 3,018 |
| weighted | 1920–24 | Vote-weighted | 16.74 | 3,048 |
| weighted | 1924–28 | Vote-weighted | 31.49 | 3,083 |
| weighted | 1928–32 | Vote-weighted | 20.79 | 3,095 |
| weighted | 1932–36 | Vote-weighted | 14.55 | 3,095 |
| weighted | 1936–40 | Vote-weighted | 12.05 | 3,094 |
| weighted | 1940–44 | Vote-weighted | 6.44 | 3,093 |
| weighted | 1944–48 | Vote-weighted | 11.85 | 3,095 |
| weighted | 1948–52 | Vote-weighted | 13.28 | 3,094 |
| weighted | 1952–56 | Vote-weighted | 10.04 | 3,097 |
| weighted | 1956–60 | Vote-weighted | 14.58 | 3,100 |
| weighted | 1960–64 | Vote-weighted | 21.24 | 3,102 |
| weighted | 1964–68 | Vote-weighted | 21.29 | 3,107 |
| weighted | 1968–72 | Vote-weighted | 17.72 | 3,109 |
| weighted | 1972–76 | Vote-weighted | 19.29 | 3,110 |
| weighted | 1976–80 | Vote-weighted | 10.90 | 3,112 |
| weighted | 1980–84 | Vote-weighted | 11.19 | 3,112 |
| weighted | 1984–88 | Vote-weighted | 6.15 | 3,114 |
| weighted | 1988–92 | Vote-weighted | 7.61 | 3,114 |
| weighted | 1992–96 | Vote-weighted | 7.86 | 3,114 |
| weighted | 1996–2000 | Vote-weighted | 7.85 | 3,113 |
| weighted | 2000–04 | Vote-weighted | 6.13 | 3,113 |
| weighted | 2004–08 | Vote-weighted | 7.68 | 3,114 |
| weighted | 2008–12 | Vote-weighted | 4.97 | 3,114 |
| weighted | 2012–16 | Vote-weighted | 10.81 | 3,112 |
| weighted | 2016–20 | Vote-weighted | 5.70 | 3,113 |
| weighted | 2020–24 | Vote-weighted | 4.47 | 3,111 |
| both | 1868–72 | Vote-weighted | 31.88 | 1,687 |
| both | 1872–76 | Vote-weighted | 29.11 | 2,151 |
| both | 1876–80 | Vote-weighted | 12.83 | 2,216 |
| both | 1880–84 | Vote-weighted | 11.84 | 2,283 |
| both | 1884–88 | Vote-weighted | 10.25 | 2,345 |
| both | 1888–92 | Vote-weighted | 17.31 | 2,424 |
| both | 1892–96 | Vote-weighted | 39.03 | 2,654 |
| both | 1896–1900 | Vote-weighted | 22.85 | 2,695 |
| both | 1900–04 | Vote-weighted | 16.53 | 2,680 |
| both | 1904–08 | Vote-weighted | 14.91 | 2,707 |
| both | 1908–12 | Vote-weighted | 23.94 | 2,832 |
| both | 1912–16 | Vote-weighted | 26.08 | 2,942 |
| both | 1916–20 | Vote-weighted | 17.04 | 3,018 |
| both | 1920–24 | Vote-weighted | 16.74 | 3,048 |
| both | 1924–28 | Vote-weighted | 31.49 | 3,083 |
| both | 1928–32 | Vote-weighted | 20.79 | 3,095 |
| both | 1932–36 | Vote-weighted | 14.55 | 3,095 |
| both | 1936–40 | Vote-weighted | 12.05 | 3,094 |
| both | 1940–44 | Vote-weighted | 6.44 | 3,093 |
| both | 1944–48 | Vote-weighted | 11.85 | 3,095 |
| both | 1948–52 | Vote-weighted | 13.28 | 3,094 |
| both | 1952–56 | Vote-weighted | 10.04 | 3,097 |
| both | 1956–60 | Vote-weighted | 14.58 | 3,100 |
| both | 1960–64 | Vote-weighted | 21.24 | 3,102 |
| both | 1964–68 | Vote-weighted | 21.29 | 3,107 |
| both | 1968–72 | Vote-weighted | 17.72 | 3,109 |
| both | 1972–76 | Vote-weighted | 19.29 | 3,110 |
| both | 1976–80 | Vote-weighted | 10.90 | 3,112 |
| both | 1980–84 | Vote-weighted | 11.19 | 3,112 |
| both | 1984–88 | Vote-weighted | 6.15 | 3,114 |
| both | 1988–92 | Vote-weighted | 7.61 | 3,114 |
| both | 1992–96 | Vote-weighted | 7.86 | 3,114 |
| both | 1996–2000 | Vote-weighted | 7.85 | 3,113 |
| both | 2000–04 | Vote-weighted | 6.13 | 3,113 |
| both | 2004–08 | Vote-weighted | 7.68 | 3,114 |
| both | 2008–12 | Vote-weighted | 4.97 | 3,114 |
| both | 2012–16 | Vote-weighted | 10.81 | 3,112 |
| both | 2016–20 | Vote-weighted | 5.70 | 3,113 |
| both | 2020–24 | Vote-weighted | 4.47 | 3,111 |
| both | 1868–72 | Each county counted once | 40.76 | 1,687 |
| both | 1872–76 | Each county counted once | 29.19 | 2,151 |
| both | 1876–80 | Each county counted once | 18.71 | 2,216 |
| both | 1880–84 | Each county counted once | 16.52 | 2,283 |
| both | 1884–88 | Each county counted once | 16.63 | 2,345 |
| both | 1888–92 | Each county counted once | 30.51 | 2,424 |
| both | 1892–96 | Each county counted once | 49.35 | 2,654 |
| both | 1896–1900 | Each county counted once | 25.60 | 2,695 |
| both | 1900–04 | Each county counted once | 23.91 | 2,680 |
| both | 1904–08 | Each county counted once | 18.98 | 2,707 |
| both | 1908–12 | Each county counted once | 27.53 | 2,832 |
| both | 1912–16 | Each county counted once | 26.23 | 2,942 |
| both | 1916–20 | Each county counted once | 21.79 | 3,018 |
| both | 1920–24 | Each county counted once | 18.48 | 3,048 |
| both | 1924–28 | Each county counted once | 36.48 | 3,083 |
| both | 1928–32 | Each county counted once | 23.56 | 3,095 |
| both | 1932–36 | Each county counted once | 14.41 | 3,095 |
| both | 1936–40 | Each county counted once | 16.03 | 3,094 |
| both | 1940–44 | Each county counted once | 8.90 | 3,093 |
| both | 1944–48 | Each county counted once | 16.75 | 3,095 |
| both | 1948–52 | Each county counted once | 18.50 | 3,094 |
| both | 1952–56 | Each county counted once | 15.20 | 3,097 |
| both | 1956–60 | Each county counted once | 17.14 | 3,100 |
| both | 1960–64 | Each county counted once | 36.80 | 3,102 |
| both | 1964–68 | Each county counted once | 37.96 | 3,107 |
| both | 1968–72 | Each county counted once | 27.04 | 3,109 |
| both | 1972–76 | Each county counted once | 25.91 | 3,110 |
| both | 1976–80 | Each county counted once | 12.75 | 3,112 |
| both | 1980–84 | Each county counted once | 14.79 | 3,112 |
| both | 1984–88 | Each county counted once | 8.57 | 3,114 |
| both | 1988–92 | Each county counted once | 10.12 | 3,114 |
| both | 1992–96 | Each county counted once | 8.22 | 3,114 |
| both | 1996–2000 | Each county counted once | 9.40 | 3,113 |
| both | 2000–04 | Each county counted once | 7.25 | 3,113 |
| both | 2004–08 | Each county counted once | 10.18 | 3,114 |
| both | 2008–12 | Each county counted once | 6.23 | 3,114 |
| both | 2012–16 | Each county counted once | 10.44 | 3,112 |
| both | 2016–20 | Each county counted once | 5.19 | 3,113 |
| both | 2020–24 | Each county counted once | 3.36 | 3,111 |

Views: Weighted by votes (view = weighted); Votes and counties (view = both).

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/dispersion_series.json

### Table 2. Relative county swings lay far from zero in early pairs and sat in a narrow band just above zero in 2020 to 2024

Relative swing is a county's swing in the Democratic minus Republican margin minus the national swing, percentage points; height is the share of a pair's votes in each 2-point bin, nine pairs of presidential elections

| Pair of elections | Bin center (points) | Share of votes (%) |
| --- | ---: | ---: |
| 1872–76 | −59 | 0.01 |
| 1872–76 | −57 | 0.00 |
| 1872–76 | −55 | 0.56 |
| 1872–76 | −53 | 0.05 |
| 1872–76 | −51 | 0.06 |
| 1872–76 | −49 | 0.02 |
| 1872–76 | −47 | 0.15 |
| 1872–76 | −45 | 0.04 |
| 1872–76 | −43 | 0.13 |
| 1872–76 | −41 | 0.06 |
| 1872–76 | −39 | 0.15 |
| 1872–76 | −37 | 0.08 |
| 1872–76 | −35 | 0.05 |
| 1872–76 | −33 | 0.15 |
| 1872–76 | −31 | 0.10 |
| 1872–76 | −29 | 0.23 |
| 1872–76 | −27 | 1.29 |
| 1872–76 | −25 | 0.38 |
| 1872–76 | −23 | 0.91 |
| 1872–76 | −21 | 1.60 |
| 1872–76 | −19 | 2.39 |
| 1872–76 | −17 | 3.03 |
| 1872–76 | −15 | 4.91 |
| 1872–76 | −13 | 6.25 |
| 1872–76 | −11 | 8.41 |
| 1872–76 | −9 | 6.32 |
| 1872–76 | −7 | 5.53 |
| 1872–76 | −5 | 6.06 |
| 1872–76 | −3 | 8.93 |
| 1872–76 | −1 | 4.71 |
| 1872–76 | +1 | 5.20 |
| 1872–76 | +3 | 3.39 |
| 1872–76 | +5 | 2.84 |
| 1872–76 | +7 | 2.46 |
| 1872–76 | +9 | 1.55 |
| 1872–76 | +11 | 1.53 |
| 1872–76 | +13 | 1.20 |
| 1872–76 | +15 | 0.64 |
| 1872–76 | +17 | 0.40 |
| 1872–76 | +19 | 0.57 |
| 1872–76 | +21 | 2.02 |
| 1872–76 | +23 | 0.50 |
| 1872–76 | +25 | 0.34 |
| 1872–76 | +27 | 0.37 |
| 1872–76 | +29 | 0.29 |
| 1872–76 | +31 | 0.34 |
| 1872–76 | +33 | 0.39 |
| 1872–76 | +35 | 0.29 |
| 1872–76 | +37 | 0.17 |
| 1872–76 | +39 | 0.33 |
| 1872–76 | +41 | 0.42 |
| 1872–76 | +43 | 0.16 |
| 1872–76 | +45 | 0.35 |
| 1872–76 | +47 | 0.21 |
| 1872–76 | +49 | 0.33 |
| 1872–76 | +51 | 0.35 |
| 1872–76 | +53 | 0.37 |
| 1872–76 | +55 | 0.13 |
| 1872–76 | +57 | 0.29 |
| 1872–76 | +59 | 0.34 |
| 1892–96 | −59 | 0.03 |
| 1892–96 | −57 | 0.10 |
| 1892–96 | −55 | 0.13 |
| 1892–96 | −53 | 0.17 |
| 1892–96 | −51 | 0.06 |
| 1892–96 | −49 | 0.04 |
| 1892–96 | −47 | 0.31 |
| 1892–96 | −45 | 0.03 |
| 1892–96 | −43 | 0.33 |
| 1892–96 | −41 | 0.15 |
| 1892–96 | −39 | 0.47 |
| 1892–96 | −37 | 1.13 |
| 1892–96 | −35 | 0.37 |
| 1892–96 | −33 | 0.67 |
| 1892–96 | −31 | 1.39 |
| 1892–96 | −29 | 0.61 |
| 1892–96 | −27 | 0.94 |
| 1892–96 | −25 | 3.79 |
| 1892–96 | −23 | 4.79 |
| 1892–96 | −21 | 3.71 |
| 1892–96 | −19 | 2.95 |
| 1892–96 | −17 | 1.22 |
| 1892–96 | −15 | 2.40 |
| 1892–96 | −13 | 1.99 |
| 1892–96 | −11 | 1.78 |
| 1892–96 | −9 | 3.55 |
| 1892–96 | −7 | 2.70 |
| 1892–96 | −5 | 5.26 |
| 1892–96 | −3 | 3.25 |
| 1892–96 | −1 | 5.92 |
| 1892–96 | +1 | 4.88 |
| 1892–96 | +3 | 3.98 |
| 1892–96 | +5 | 3.71 |
| 1892–96 | +7 | 4.95 |
| 1892–96 | +9 | 3.67 |
| 1892–96 | +11 | 3.57 |
| 1892–96 | +13 | 2.96 |
| 1892–96 | +15 | 2.38 |
| 1892–96 | +17 | 1.44 |
| 1892–96 | +19 | 1.47 |
| 1892–96 | +21 | 0.69 |
| 1892–96 | +23 | 0.80 |
| 1892–96 | +25 | 1.08 |
| 1892–96 | +27 | 0.57 |
| 1892–96 | +29 | 0.40 |
| 1892–96 | +31 | 0.25 |
| 1892–96 | +33 | 0.16 |
| 1892–96 | +35 | 0.55 |
| 1892–96 | +37 | 0.33 |
| 1892–96 | +39 | 0.19 |
| 1892–96 | +41 | 0.28 |
| 1892–96 | +43 | 0.17 |
| 1892–96 | +45 | 0.24 |
| 1892–96 | +47 | 0.13 |
| 1892–96 | +49 | 0.08 |
| 1892–96 | +51 | 0.16 |
| 1892–96 | +53 | 0.22 |
| 1892–96 | +55 | 0.13 |
| 1892–96 | +57 | 0.06 |
| 1892–96 | +59 | 0.23 |
| 1912–16 | −59 | 0.22 |
| 1912–16 | −57 | 0.12 |
| 1912–16 | −55 | 0.28 |
| 1912–16 | −53 | 0.15 |
| 1912–16 | −51 | 0.06 |
| 1912–16 | −49 | 0.19 |
| 1912–16 | −47 | 0.58 |
| 1912–16 | −45 | 0.39 |
| 1912–16 | −43 | 0.32 |
| 1912–16 | −41 | 0.28 |
| 1912–16 | −39 | 0.05 |
| 1912–16 | −37 | 0.69 |
| 1912–16 | −35 | 0.29 |
| 1912–16 | −33 | 0.76 |
| 1912–16 | −31 | 0.64 |
| 1912–16 | −29 | 1.54 |
| 1912–16 | −27 | 1.03 |
| 1912–16 | −25 | 0.75 |
| 1912–16 | −23 | 1.16 |
| 1912–16 | −21 | 1.22 |
| 1912–16 | −19 | 1.89 |
| 1912–16 | −17 | 1.78 |
| 1912–16 | −15 | 2.36 |
| 1912–16 | −13 | 1.61 |
| 1912–16 | −11 | 2.12 |
| 1912–16 | −9 | 11.26 |
| 1912–16 | −7 | 2.83 |
| 1912–16 | −5 | 2.36 |
| 1912–16 | −3 | 1.67 |
| 1912–16 | −1 | 2.50 |
| 1912–16 | +1 | 2.69 |
| 1912–16 | +3 | 2.47 |
| 1912–16 | +5 | 4.58 |
| 1912–16 | +7 | 4.85 |
| 1912–16 | +9 | 3.33 |
| 1912–16 | +11 | 3.17 |
| 1912–16 | +13 | 4.13 |
| 1912–16 | +15 | 3.24 |
| 1912–16 | +17 | 3.95 |
| 1912–16 | +19 | 3.85 |
| 1912–16 | +21 | 2.13 |
| 1912–16 | +23 | 2.77 |
| 1912–16 | +25 | 2.18 |
| 1912–16 | +27 | 3.12 |
| 1912–16 | +29 | 1.55 |
| 1912–16 | +31 | 1.01 |
| 1912–16 | +33 | 0.63 |
| 1912–16 | +35 | 1.20 |
| 1912–16 | +37 | 0.38 |
| 1912–16 | +39 | 0.27 |
| 1912–16 | +41 | 0.16 |
| 1912–16 | +43 | 0.32 |
| 1912–16 | +45 | 0.21 |
| 1912–16 | +47 | 0.18 |
| 1912–16 | +49 | 0.13 |
| 1912–16 | +51 | 0.10 |
| 1912–16 | +53 | 0.07 |
| 1912–16 | +55 | 0.20 |
| 1912–16 | +57 | 0.03 |
| 1912–16 | +59 | 0.07 |
| 1932–36 | −59 | 0.00 |
| 1932–36 | −57 | 0.01 |
| 1932–36 | −55 | 0.00 |
| 1932–36 | −53 | 0.03 |
| 1932–36 | −51 | 0.00 |
| 1932–36 | −49 | 0.01 |
| 1932–36 | −47 | 0.02 |
| 1932–36 | −45 | 0.04 |
| 1932–36 | −43 | 0.04 |
| 1932–36 | −41 | 0.06 |
| 1932–36 | −39 | 0.10 |
| 1932–36 | −37 | 0.31 |
| 1932–36 | −35 | 0.24 |
| 1932–36 | −33 | 0.46 |
| 1932–36 | −31 | 0.44 |
| 1932–36 | −29 | 0.71 |
| 1932–36 | −27 | 1.11 |
| 1932–36 | −25 | 1.51 |
| 1932–36 | −23 | 1.15 |
| 1932–36 | −21 | 1.86 |
| 1932–36 | −19 | 2.11 |
| 1932–36 | −17 | 2.38 |
| 1932–36 | −15 | 2.98 |
| 1932–36 | −13 | 2.77 |
| 1932–36 | −11 | 3.84 |
| 1932–36 | −9 | 2.73 |
| 1932–36 | −7 | 3.72 |
| 1932–36 | −5 | 7.98 |
| 1932–36 | −3 | 7.22 |
| 1932–36 | −1 | 6.08 |
| 1932–36 | +1 | 2.85 |
| 1932–36 | +3 | 5.23 |
| 1932–36 | +5 | 3.83 |
| 1932–36 | +7 | 8.02 |
| 1932–36 | +9 | 6.06 |
| 1932–36 | +11 | 7.33 |
| 1932–36 | +13 | 2.14 |
| 1932–36 | +15 | 2.38 |
| 1932–36 | +17 | 2.71 |
| 1932–36 | +19 | 1.56 |
| 1932–36 | +21 | 0.69 |
| 1932–36 | +23 | 0.94 |
| 1932–36 | +25 | 1.00 |
| 1932–36 | +27 | 0.49 |
| 1932–36 | +29 | 3.36 |
| 1932–36 | +31 | 0.42 |
| 1932–36 | +33 | 0.00 |
| 1932–36 | +35 | 0.00 |
| 1932–36 | +37 | 0.16 |
| 1932–36 | +39 | 0.22 |
| 1932–36 | +41 | 0.28 |
| 1932–36 | +43 | 0.03 |
| 1932–36 | +45 | 0.00 |
| 1932–36 | +47 | 0.20 |
| 1932–36 | +49 | 0.00 |
| 1932–36 | +51 | 0.08 |
| 1932–36 | +53 | 0.00 |
| 1932–36 | +55 | 0.00 |
| 1932–36 | +57 | 0.00 |
| 1932–36 | +59 | 0.00 |
| 1952–56 | −59 | 0.01 |
| 1952–56 | −57 | 0.01 |
| 1952–56 | −55 | 0.02 |
| 1952–56 | −53 | 0.01 |
| 1952–56 | −51 | 0.00 |
| 1952–56 | −49 | 0.00 |
| 1952–56 | −47 | 0.04 |
| 1952–56 | −45 | 0.02 |
| 1952–56 | −43 | 0.01 |
| 1952–56 | −41 | 0.03 |
| 1952–56 | −39 | 0.02 |
| 1952–56 | −37 | 0.01 |
| 1952–56 | −35 | 0.01 |
| 1952–56 | −33 | 0.03 |
| 1952–56 | −31 | 0.01 |
| 1952–56 | −29 | 0.03 |
| 1952–56 | −27 | 0.06 |
| 1952–56 | −25 | 0.60 |
| 1952–56 | −23 | 0.18 |
| 1952–56 | −21 | 0.21 |
| 1952–56 | −19 | 0.37 |
| 1952–56 | −17 | 0.51 |
| 1952–56 | −15 | 0.94 |
| 1952–56 | −13 | 2.41 |
| 1952–56 | −11 | 4.47 |
| 1952–56 | −9 | 8.54 |
| 1952–56 | −7 | 6.62 |
| 1952–56 | −5 | 7.28 |
| 1952–56 | −3 | 8.11 |
| 1952–56 | −1 | 6.47 |
| 1952–56 | +1 | 10.87 |
| 1952–56 | +3 | 4.37 |
| 1952–56 | +5 | 13.83 |
| 1952–56 | +7 | 7.39 |
| 1952–56 | +9 | 3.87 |
| 1952–56 | +11 | 3.39 |
| 1952–56 | +13 | 1.94 |
| 1952–56 | +15 | 2.02 |
| 1952–56 | +17 | 1.12 |
| 1952–56 | +19 | 1.05 |
| 1952–56 | +21 | 0.89 |
| 1952–56 | +23 | 0.58 |
| 1952–56 | +25 | 0.56 |
| 1952–56 | +27 | 0.21 |
| 1952–56 | +29 | 0.27 |
| 1952–56 | +31 | 0.10 |
| 1952–56 | +33 | 0.05 |
| 1952–56 | +35 | 0.07 |
| 1952–56 | +37 | 0.07 |
| 1952–56 | +39 | 0.02 |
| 1952–56 | +41 | 0.02 |
| 1952–56 | +43 | 0.02 |
| 1952–56 | +45 | 0.00 |
| 1952–56 | +47 | 0.00 |
| 1952–56 | +49 | 0.00 |
| 1952–56 | +51 | 0.01 |
| 1952–56 | +53 | 0.00 |
| 1952–56 | +55 | 0.00 |
| 1952–56 | +57 | 0.01 |
| 1952–56 | +59 | 0.00 |
| 1972–76 | −59 | 0.00 |
| 1972–76 | −57 | 0.00 |
| 1972–76 | −55 | 0.00 |
| 1972–76 | −53 | 0.00 |
| 1972–76 | −51 | 0.01 |
| 1972–76 | −49 | 0.00 |
| 1972–76 | −47 | 0.00 |
| 1972–76 | −45 | 0.00 |
| 1972–76 | −43 | 0.00 |
| 1972–76 | −41 | 0.23 |
| 1972–76 | −39 | 0.01 |
| 1972–76 | −37 | 0.00 |
| 1972–76 | −35 | 0.13 |
| 1972–76 | −33 | 0.15 |
| 1972–76 | −31 | 0.53 |
| 1972–76 | −29 | 0.27 |
| 1972–76 | −27 | 0.56 |
| 1972–76 | −25 | 0.50 |
| 1972–76 | −23 | 1.27 |
| 1972–76 | −21 | 1.42 |
| 1972–76 | −19 | 1.76 |
| 1972–76 | −17 | 4.16 |
| 1972–76 | −15 | 3.96 |
| 1972–76 | −13 | 4.54 |
| 1972–76 | −11 | 10.97 |
| 1972–76 | −9 | 9.86 |
| 1972–76 | −7 | 4.73 |
| 1972–76 | −5 | 4.16 |
| 1972–76 | −3 | 6.08 |
| 1972–76 | −1 | 3.83 |
| 1972–76 | +1 | 3.49 |
| 1972–76 | +3 | 4.15 |
| 1972–76 | +5 | 2.25 |
| 1972–76 | +7 | 3.87 |
| 1972–76 | +9 | 3.85 |
| 1972–76 | +11 | 3.14 |
| 1972–76 | +13 | 1.31 |
| 1972–76 | +15 | 1.95 |
| 1972–76 | +17 | 1.64 |
| 1972–76 | +19 | 1.06 |
| 1972–76 | +21 | 0.99 |
| 1972–76 | +23 | 1.73 |
| 1972–76 | +25 | 1.20 |
| 1972–76 | +27 | 0.92 |
| 1972–76 | +29 | 0.85 |
| 1972–76 | +31 | 0.97 |
| 1972–76 | +33 | 0.52 |
| 1972–76 | +35 | 0.84 |
| 1972–76 | +37 | 0.62 |
| 1972–76 | +39 | 0.51 |
| 1972–76 | +41 | 0.61 |
| 1972–76 | +43 | 0.39 |
| 1972–76 | +45 | 0.39 |
| 1972–76 | +47 | 0.34 |
| 1972–76 | +49 | 0.37 |
| 1972–76 | +51 | 0.26 |
| 1972–76 | +53 | 0.23 |
| 1972–76 | +55 | 0.20 |
| 1972–76 | +57 | 0.38 |
| 1972–76 | +59 | 0.12 |
| 1992–96 | −59 | 0.00 |
| 1992–96 | −57 | 0.00 |
| 1992–96 | −55 | 0.00 |
| 1992–96 | −53 | 0.00 |
| 1992–96 | −51 | 0.00 |
| 1992–96 | −49 | 0.00 |
| 1992–96 | −47 | 0.00 |
| 1992–96 | −45 | 0.00 |
| 1992–96 | −43 | 0.00 |
| 1992–96 | −41 | 0.00 |
| 1992–96 | −39 | 0.00 |
| 1992–96 | −37 | 0.00 |
| 1992–96 | −35 | 0.00 |
| 1992–96 | −33 | 0.02 |
| 1992–96 | −31 | 0.02 |
| 1992–96 | −29 | 0.01 |
| 1992–96 | −27 | 0.02 |
| 1992–96 | −25 | 0.06 |
| 1992–96 | −23 | 0.05 |
| 1992–96 | −21 | 0.36 |
| 1992–96 | −19 | 0.43 |
| 1992–96 | −17 | 0.40 |
| 1992–96 | −15 | 1.22 |
| 1992–96 | −13 | 2.14 |
| 1992–96 | −11 | 2.31 |
| 1992–96 | −9 | 4.32 |
| 1992–96 | −7 | 7.22 |
| 1992–96 | −5 | 6.41 |
| 1992–96 | −3 | 9.24 |
| 1992–96 | −1 | 10.91 |
| 1992–96 | +1 | 13.27 |
| 1992–96 | +3 | 9.34 |
| 1992–96 | +5 | 6.44 |
| 1992–96 | +7 | 6.25 |
| 1992–96 | +9 | 4.87 |
| 1992–96 | +11 | 4.88 |
| 1992–96 | +13 | 3.78 |
| 1992–96 | +15 | 3.93 |
| 1992–96 | +17 | 1.13 |
| 1992–96 | +19 | 0.52 |
| 1992–96 | +21 | 0.19 |
| 1992–96 | +23 | 0.00 |
| 1992–96 | +25 | 0.01 |
| 1992–96 | +27 | 0.21 |
| 1992–96 | +29 | 0.01 |
| 1992–96 | +31 | 0.00 |
| 1992–96 | +33 | 0.00 |
| 1992–96 | +35 | 0.00 |
| 1992–96 | +37 | 0.00 |
| 1992–96 | +39 | 0.00 |
| 1992–96 | +41 | 0.00 |
| 1992–96 | +43 | 0.00 |
| 1992–96 | +45 | 0.00 |
| 1992–96 | +47 | 0.00 |
| 1992–96 | +49 | 0.00 |
| 1992–96 | +51 | 0.00 |
| 1992–96 | +53 | 0.00 |
| 1992–96 | +55 | 0.00 |
| 1992–96 | +57 | 0.00 |
| 1992–96 | +59 | 0.00 |
| 2012–16 | −59 | 0.00 |
| 2012–16 | −57 | 0.00 |
| 2012–16 | −55 | 0.00 |
| 2012–16 | −53 | 0.00 |
| 2012–16 | −51 | 0.00 |
| 2012–16 | −49 | 0.00 |
| 2012–16 | −47 | 0.00 |
| 2012–16 | −45 | 0.00 |
| 2012–16 | −43 | 0.00 |
| 2012–16 | −41 | 0.01 |
| 2012–16 | −39 | 0.01 |
| 2012–16 | −37 | 0.03 |
| 2012–16 | −35 | 0.08 |
| 2012–16 | −33 | 0.11 |
| 2012–16 | −31 | 0.28 |
| 2012–16 | −29 | 0.49 |
| 2012–16 | −27 | 0.49 |
| 2012–16 | −25 | 0.72 |
| 2012–16 | −23 | 1.21 |
| 2012–16 | −21 | 1.13 |
| 2012–16 | −19 | 1.41 |
| 2012–16 | −17 | 2.19 |
| 2012–16 | −15 | 2.64 |
| 2012–16 | −13 | 2.38 |
| 2012–16 | −11 | 4.13 |
| 2012–16 | −9 | 3.47 |
| 2012–16 | −7 | 6.19 |
| 2012–16 | −5 | 5.31 |
| 2012–16 | −3 | 5.33 |
| 2012–16 | −1 | 9.77 |
| 2012–16 | +1 | 4.89 |
| 2012–16 | +3 | 7.38 |
| 2012–16 | +5 | 7.62 |
| 2012–16 | +7 | 6.08 |
| 2012–16 | +9 | 7.27 |
| 2012–16 | +11 | 6.75 |
| 2012–16 | +13 | 3.44 |
| 2012–16 | +15 | 5.03 |
| 2012–16 | +17 | 2.72 |
| 2012–16 | +19 | 0.78 |
| 2012–16 | +21 | 0.11 |
| 2012–16 | +23 | 0.01 |
| 2012–16 | +25 | 0.21 |
| 2012–16 | +27 | 0.00 |
| 2012–16 | +29 | 0.09 |
| 2012–16 | +31 | 0.00 |
| 2012–16 | +33 | 0.00 |
| 2012–16 | +35 | 0.25 |
| 2012–16 | +37 | 0.00 |
| 2012–16 | +39 | 0.00 |
| 2012–16 | +41 | 0.00 |
| 2012–16 | +43 | 0.00 |
| 2012–16 | +45 | 0.00 |
| 2012–16 | +47 | 0.00 |
| 2012–16 | +49 | 0.00 |
| 2012–16 | +51 | 0.00 |
| 2012–16 | +53 | 0.00 |
| 2012–16 | +55 | 0.00 |
| 2012–16 | +57 | 0.00 |
| 2012–16 | +59 | 0.00 |
| 2020–24 | −59 | 0.00 |
| 2020–24 | −57 | 0.00 |
| 2020–24 | −55 | 0.00 |
| 2020–24 | −53 | 0.00 |
| 2020–24 | −51 | 0.00 |
| 2020–24 | −49 | 0.00 |
| 2020–24 | −47 | 0.00 |
| 2020–24 | −45 | 0.00 |
| 2020–24 | −43 | 0.00 |
| 2020–24 | −41 | 0.00 |
| 2020–24 | −39 | 0.00 |
| 2020–24 | −37 | 0.00 |
| 2020–24 | −35 | 0.00 |
| 2020–24 | −33 | 0.00 |
| 2020–24 | −31 | 0.00 |
| 2020–24 | −29 | 0.00 |
| 2020–24 | −27 | 0.00 |
| 2020–24 | −25 | 0.00 |
| 2020–24 | −23 | 0.01 |
| 2020–24 | −21 | 0.13 |

The first 500 of 540 rows; every row is in https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/swing_distribution.json.

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Note: The bins run from minus 60 to plus 60 points and swings beyond that range are not drawn; 1892 to 1896 has the largest share beyond it among the pairs shown.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/swing_distribution.json

### Table 3. The share of counties within 5 points of the national swing rose from 21.2% in 1972 to 1976 to 75.6% in 2020 to 2024

Change in each county's Democratic minus Republican margin, minus the national change, percentage points, for each of 39 pairs of presidential elections

No inline rows: the values of Table 3 are in https://vishalsingh.org/politics/data/nationalization-of-the-county-vote/swing_map.json.

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Note: Counties are drawn on 2020 boundaries and matched across elections on FIPS code. A county with no return in one of the two elections, or whose code is absent from the 2020 map, draws as no data. Values are rounded to one decimal place, except that a county within 5 points of the national swing is never rounded to the edge of the palest class, so that class holds the counties counted in the text.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/swing_map.json

### Table 4. The share of votes near the national swing was 73.3% in 2008 to 2012 and 73.1% in 2020 to 2024, the two highest of 39 pairs

Share of votes cast in counties whose swing is within 5 points of the national swing, percent; one point per pair of consecutive presidential elections, plotted at the later election

| Counted by | Pair of elections | Reference swing | Share within the band (%) | Counties |
| --- | --- | --- | ---: | ---: |
| Votes | 1868–72 | National swing | 22.5 | 1,687 |
| Votes | 1868–72 | Mean county swing | 22.7 | 1,687 |
| Counties | 1868–72 | National swing | 16.5 | 1,687 |
| Counties | 1868–72 | Mean county swing | 16.7 | 1,687 |
| Votes | 1872–76 | National swing | 26.1 | 2,151 |
| Votes | 1872–76 | Mean county swing | 16.8 | 2,151 |
| Counties | 1872–76 | National swing | 22.9 | 2,151 |
| Counties | 1872–76 | Mean county swing | 17.4 | 2,151 |
| Votes | 1876–80 | National swing | 61.1 | 2,216 |
| Votes | 1876–80 | Mean county swing | 60.4 | 2,216 |
| Counties | 1876–80 | National swing | 47.9 | 2,216 |
| Counties | 1876–80 | Mean county swing | 47.7 | 2,216 |
| Votes | 1880–84 | National swing | 51.5 | 2,283 |
| Votes | 1880–84 | Mean county swing | 51.5 | 2,283 |
| Counties | 1880–84 | National swing | 39.5 | 2,283 |
| Counties | 1880–84 | Mean county swing | 39.5 | 2,283 |
| Votes | 1884–88 | National swing | 60.8 | 2,345 |
| Votes | 1884–88 | Mean county swing | 58.7 | 2,345 |
| Counties | 1884–88 | National swing | 50.1 | 2,345 |
| Counties | 1884–88 | Mean county swing | 48.3 | 2,345 |
| Votes | 1888–92 | National swing | 60.6 | 2,424 |
| Votes | 1888–92 | Mean county swing | 61.6 | 2,424 |
| Counties | 1888–92 | National swing | 43.5 | 2,424 |
| Counties | 1888–92 | Mean county swing | 44.1 | 2,424 |
| Votes | 1892–96 | National swing | 22.7 | 2,654 |
| Votes | 1892–96 | Mean county swing | 23.6 | 2,654 |
| Counties | 1892–96 | National swing | 18.4 | 2,654 |
| Counties | 1892–96 | Mean county swing | 21.3 | 2,654 |
| Votes | 1896–1900 | National swing | 37.8 | 2,695 |
| Votes | 1896–1900 | Mean county swing | 32.6 | 2,695 |
| Counties | 1896–1900 | National swing | 30.1 | 2,695 |
| Counties | 1896–1900 | Mean county swing | 25.3 | 2,695 |
| Votes | 1900–04 | National swing | 29.1 | 2,680 |
| Votes | 1900–04 | Mean county swing | 28.3 | 2,680 |
| Counties | 1900–04 | National swing | 21.2 | 2,680 |
| Counties | 1900–04 | Mean county swing | 22.0 | 2,680 |
| Votes | 1904–08 | National swing | 25.4 | 2,707 |
| Votes | 1904–08 | Mean county swing | 25.2 | 2,707 |
| Counties | 1904–08 | National swing | 23.1 | 2,707 |
| Counties | 1904–08 | Mean county swing | 22.8 | 2,707 |
| Votes | 1908–12 | National swing | 16.8 | 2,832 |
| Votes | 1908–12 | Mean county swing | 17.7 | 2,832 |
| Counties | 1908–12 | National swing | 14.8 | 2,832 |
| Counties | 1908–12 | Mean county swing | 15.8 | 2,832 |
| Votes | 1912–16 | National swing | 11.7 | 2,942 |
| Votes | 1912–16 | Mean county swing | 11.5 | 2,942 |
| Counties | 1912–16 | National swing | 12.7 | 2,942 |
| Counties | 1912–16 | Mean county swing | 11.9 | 2,942 |
| Votes | 1916–20 | National swing | 21.4 | 3,018 |
| Votes | 1916–20 | Mean county swing | 23.1 | 3,018 |
| Counties | 1916–20 | National swing | 15.8 | 3,018 |
| Counties | 1916–20 | Mean county swing | 15.9 | 3,018 |
| Votes | 1920–24 | National swing | 30.6 | 3,048 |
| Votes | 1920–24 | Mean county swing | 30.7 | 3,048 |
| Counties | 1920–24 | National swing | 24.8 | 3,048 |
| Counties | 1920–24 | Mean county swing | 25.1 | 3,048 |
| Votes | 1924–28 | National swing | 10.7 | 3,083 |
| Votes | 1924–28 | Mean county swing | 9.9 | 3,083 |
| Counties | 1924–28 | National swing | 8.5 | 3,083 |
| Counties | 1924–28 | Mean county swing | 7.9 | 3,083 |
| Votes | 1928–32 | National swing | 16.9 | 3,095 |
| Votes | 1928–32 | Mean county swing | 16.7 | 3,095 |
| Counties | 1928–32 | National swing | 17.0 | 3,095 |
| Counties | 1928–32 | Mean county swing | 16.5 | 3,095 |
| Votes | 1932–36 | National swing | 28.1 | 3,095 |
| Votes | 1932–36 | Mean county swing | 27.0 | 3,095 |
| Counties | 1932–36 | National swing | 22.6 | 3,095 |
| Counties | 1932–36 | Mean county swing | 20.8 | 3,095 |
| Votes | 1936–40 | National swing | 41.0 | 3,094 |
| Votes | 1936–40 | Mean county swing | 39.9 | 3,094 |
| Counties | 1936–40 | National swing | 25.0 | 3,094 |
| Counties | 1936–40 | Mean county swing | 24.4 | 3,094 |
| Votes | 1940–44 | National swing | 62.0 | 3,093 |
| Votes | 1940–44 | Mean county swing | 62.4 | 3,093 |
| Counties | 1940–44 | National swing | 54.3 | 3,093 |
| Counties | 1940–44 | Mean county swing | 54.8 | 3,093 |
| Votes | 1944–48 | National swing | 32.9 | 3,095 |
| Votes | 1944–48 | Mean county swing | 32.1 | 3,095 |
| Counties | 1944–48 | National swing | 27.3 | 3,095 |
| Counties | 1944–48 | Mean county swing | 27.5 | 3,095 |
| Votes | 1948–52 | National swing | 36.7 | 3,094 |
| Votes | 1948–52 | Mean county swing | 35.3 | 3,094 |
| Counties | 1948–52 | National swing | 24.3 | 3,094 |
| Counties | 1948–52 | Mean county swing | 24.2 | 3,094 |
| Votes | 1952–56 | National swing | 39.1 | 3,097 |
| Votes | 1952–56 | Mean county swing | 40.1 | 3,097 |
| Counties | 1952–56 | National swing | 31.9 | 3,097 |
| Counties | 1952–56 | Mean county swing | 32.4 | 3,097 |
| Votes | 1956–60 | National swing | 27.1 | 3,100 |
| Votes | 1956–60 | Mean county swing | 26.9 | 3,100 |
| Counties | 1956–60 | National swing | 19.7 | 3,100 |
| Counties | 1956–60 | Mean county swing | 19.3 | 3,100 |
| Votes | 1960–64 | National swing | 29.4 | 3,102 |
| Votes | 1960–64 | Mean county swing | 29.2 | 3,102 |
| Counties | 1960–64 | National swing | 22.2 | 3,102 |
| Counties | 1960–64 | Mean county swing | 22.0 | 3,102 |
| Votes | 1964–68 | National swing | 37.1 | 3,107 |
| Votes | 1964–68 | Mean county swing | 37.5 | 3,107 |
| Counties | 1964–68 | National swing | 20.6 | 3,107 |
| Counties | 1964–68 | Mean county swing | 20.8 | 3,107 |
| Votes | 1968–72 | National swing | 28.9 | 3,109 |
| Votes | 1968–72 | Mean county swing | 33.6 | 3,109 |
| Counties | 1968–72 | National swing | 18.6 | 3,109 |
| Counties | 1968–72 | Mean county swing | 19.6 | 3,109 |
| Votes | 1972–76 | National swing | 20.3 | 3,110 |
| Votes | 1972–76 | Mean county swing | 20.4 | 3,110 |
| Counties | 1972–76 | National swing | 21.2 | 3,110 |
| Counties | 1972–76 | Mean county swing | 20.4 | 3,110 |
| Votes | 1976–80 | National swing | 37.1 | 3,112 |
| Votes | 1976–80 | Mean county swing | 37.8 | 3,112 |
| Counties | 1976–80 | National swing | 29.7 | 3,112 |
| Counties | 1976–80 | Mean county swing | 29.3 | 3,112 |
| Votes | 1980–84 | National swing | 33.7 | 3,112 |
| Votes | 1980–84 | Mean county swing | 33.6 | 3,112 |
| Counties | 1980–84 | National swing | 27.8 | 3,112 |
| Counties | 1980–84 | Mean county swing | 27.9 | 3,112 |
| Votes | 1984–88 | National swing | 61.7 | 3,114 |
| Votes | 1984–88 | Mean county swing | 62.4 | 3,114 |
| Counties | 1984–88 | National swing | 42.2 | 3,114 |
| Counties | 1984–88 | Mean county swing | 42.4 | 3,114 |
| Votes | 1988–92 | National swing | 48.6 | 3,114 |
| Votes | 1988–92 | Mean county swing | 49.6 | 3,114 |
| Counties | 1988–92 | National swing | 40.0 | 3,114 |
| Counties | 1988–92 | Mean county swing | 39.4 | 3,114 |
| Votes | 1992–96 | National swing | 48.8 | 3,114 |
| Votes | 1992–96 | Mean county swing | 48.8 | 3,114 |
| Counties | 1992–96 | National swing | 47.5 | 3,114 |
| Counties | 1992–96 | Mean county swing | 44.9 | 3,114 |
| Votes | 1996–2000 | National swing | 44.8 | 3,113 |
| Votes | 1996–2000 | Mean county swing | 46.3 | 3,113 |
| Counties | 1996–2000 | National swing | 32.2 | 3,113 |
| Counties | 1996–2000 | Mean county swing | 31.4 | 3,113 |
| Votes | 2000–04 | National swing | 61.6 | 3,113 |
| Votes | 2000–04 | Mean county swing | 61.8 | 3,113 |
| Counties | 2000–04 | National swing | 54.2 | 3,113 |
| Counties | 2000–04 | Mean county swing | 53.7 | 3,113 |
| Votes | 2004–08 | National swing | 56.5 | 3,114 |
| Votes | 2004–08 | Mean county swing | 56.1 | 3,114 |
| Counties | 2004–08 | National swing | 43.9 | 3,114 |
| Counties | 2004–08 | Mean county swing | 43.5 | 3,114 |
| Votes | 2008–12 | National swing | 73.3 | 3,114 |
| Votes | 2008–12 | Mean county swing | 73.0 | 3,114 |
| Counties | 2008–12 | National swing | 58.8 | 3,114 |
| Counties | 2008–12 | Mean county swing | 58.3 | 3,114 |
| Votes | 2012–16 | National swing | 34.0 | 3,112 |
| Votes | 2012–16 | Mean county swing | 34.2 | 3,112 |
| Counties | 2012–16 | National swing | 24.6 | 3,112 |
| Counties | 2012–16 | Mean county swing | 23.6 | 3,112 |
| Votes | 2016–20 | National swing | 69.1 | 3,113 |
| Votes | 2016–20 | Mean county swing | 69.1 | 3,113 |
| Counties | 2016–20 | National swing | 73.9 | 3,113 |
| Counties | 2016–20 | Mean county swing | 73.9 | 3,113 |
| Votes | 2020–24 | National swing | 73.1 | 3,111 |
| Votes | 2020–24 | Mean county swing | 80.0 | 3,111 |
| Counties | 2020–24 | National swing | 75.6 | 3,111 |
| Counties | 2020–24 | Mean county swing | 86.3 | 3,111 |

Views: Share of votes (basis = Votes, reference = National swing); Share of counties (basis = Counties, reference = National swing).

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Note: A county is near the national swing if its own swing differs from it by less than 5 points.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/share_near_national_swing.json

### Table 5. The spread of county swings was 33.5 points in the South and 11.4 elsewhere in 1960 to 1964, and 4.4 and 4.5 in 2020 to 2024

Standard deviation of county swings within each region, percentage points of the two-party margin, weighted by votes; one point per pair of elections, plotted at the later election

| View | Pair of elections | Region | Value (points) | Counties |
| --- | --- | --- | ---: | ---: |
| spread | 1868–72 | South | 39.98 | 670 |
| spread | 1868–72 | Rest of the country | 28.60 | 1,017 |
| offset | 1868–72 | South | −6.13 | 670 |
| offset | 1868–72 | Rest of the country | 1.02 | 1,017 |
| spread | 1872–76 | South | 23.21 | 1,059 |
| spread | 1872–76 | Rest of the country | 31.15 | 1,092 |
| offset | 1872–76 | South | 5.38 | 1,059 |
| offset | 1872–76 | Rest of the country | −1.96 | 1,092 |
| spread | 1876–80 | South | 22.54 | 1,084 |
| spread | 1876–80 | Rest of the country | 6.53 | 1,132 |
| offset | 1876–80 | South | 3.57 | 1,084 |
| offset | 1876–80 | Rest of the country | −0.47 | 1,132 |
| spread | 1880–84 | South | 16.59 | 1,106 |
| spread | 1880–84 | Rest of the country | 9.22 | 1,177 |
| offset | 1880–84 | South | −3.32 | 1,106 |
| offset | 1880–84 | Rest of the country | 1.05 | 1,177 |
| spread | 1884–88 | South | 17.09 | 1,142 |
| spread | 1884–88 | Rest of the country | 6.22 | 1,203 |
| offset | 1884–88 | South | 1.77 | 1,142 |
| offset | 1884–88 | Rest of the country | −0.39 | 1,203 |
| spread | 1888–92 | South | 23.35 | 1,164 |
| spread | 1888–92 | Rest of the country | 14.20 | 1,260 |
| offset | 1888–92 | South | 7.85 | 1,164 |
| offset | 1888–92 | Rest of the country | −1.93 | 1,260 |
| spread | 1892–96 | South | 24.96 | 1,197 |
| spread | 1892–96 | Rest of the country | 42.19 | 1,457 |
| offset | 1892–96 | South | −4.18 | 1,197 |
| offset | 1892–96 | Rest of the country | 1.29 | 1,457 |
| spread | 1896–1900 | South | 17.22 | 1,188 |
| spread | 1896–1900 | Rest of the country | 24.15 | 1,507 |
| offset | 1896–1900 | South | −0.17 | 1,188 |
| offset | 1896–1900 | Rest of the country | 0.79 | 1,507 |
| spread | 1900–04 | South | 16.19 | 1,164 |
| spread | 1900–04 | Rest of the country | 13.74 | 1,516 |
| offset | 1900–04 | South | 18.70 | 1,164 |
| offset | 1900–04 | Rest of the country | −3.18 | 1,516 |
| spread | 1904–08 | South | 12.32 | 1,185 |
| spread | 1904–08 | Rest of the country | 13.67 | 1,522 |
| offset | 1904–08 | South | −12.42 | 1,185 |
| offset | 1904–08 | Rest of the country | 2.79 | 1,522 |
| spread | 1908–12 | South | 22.53 | 1,320 |
| spread | 1908–12 | Rest of the country | 24.00 | 1,512 |
| offset | 1908–12 | South | −5.59 | 1,320 |
| offset | 1908–12 | Rest of the country | 0.38 | 1,512 |
| spread | 1912–16 | South | 23.35 | 1,356 |
| spread | 1912–16 | Rest of the country | 26.50 | 1,586 |
| offset | 1912–16 | South | 4.51 | 1,356 |
| offset | 1912–16 | Rest of the country | 0.40 | 1,586 |
| spread | 1916–20 | South | 15.08 | 1,375 |
| spread | 1916–20 | Rest of the country | 15.27 | 1,643 |
| offset | 1916–20 | South | 10.84 | 1,375 |
| offset | 1916–20 | Rest of the country | −3.53 | 1,643 |
| spread | 1920–24 | South | 14.72 | 1,382 |
| spread | 1920–24 | Rest of the country | 16.16 | 1,666 |
| offset | 1920–24 | South | 12.63 | 1,382 |
| offset | 1920–24 | Rest of the country | −2.66 | 1,666 |
| spread | 1924–28 | South | 25.15 | 1,405 |
| spread | 1924–28 | Rest of the country | 24.93 | 1,678 |
| offset | 1924–28 | South | −38.58 | 1,405 |
| offset | 1924–28 | Rest of the country | 9.72 | 1,678 |
| spread | 1928–32 | South | 24.02 | 1,411 |
| spread | 1928–32 | Rest of the country | 18.64 | 1,684 |
| offset | 1928–32 | South | 15.17 | 1,411 |
| offset | 1928–32 | Rest of the country | −3.45 | 1,684 |
| spread | 1932–36 | South | 13.20 | 1,412 |
| spread | 1932–36 | Rest of the country | 14.49 | 1,683 |
| offset | 1932–36 | South | −6.15 | 1,412 |
| offset | 1932–36 | Rest of the country | 1.58 | 1,683 |
| spread | 1936–40 | South | 10.70 | 1,411 |
| spread | 1936–40 | Rest of the country | 11.44 | 1,683 |
| offset | 1936–40 | South | 10.11 | 1,411 |
| offset | 1936–40 | Rest of the country | −1.79 | 1,683 |
| spread | 1940–44 | South | 9.64 | 1,411 |
| spread | 1940–44 | Rest of the country | 5.25 | 1,682 |
| offset | 1940–44 | South | −4.90 | 1,411 |
| offset | 1940–44 | Rest of the country | 0.95 | 1,682 |
| spread | 1944–48 | South | 17.49 | 1,412 |
| spread | 1944–48 | Rest of the country | 10.30 | 1,683 |
| offset | 1944–48 | South | −5.27 | 1,412 |
| offset | 1944–48 | Rest of the country | 1.25 | 1,683 |
| spread | 1948–52 | South | 18.79 | 1,411 |
| spread | 1948–52 | Rest of the country | 10.40 | 1,683 |
| offset | 1948–52 | South | −6.54 | 1,411 |
| offset | 1948–52 | Rest of the country | 0.39 | 1,683 |
| spread | 1952–56 | South | 13.77 | 1,414 |
| spread | 1952–56 | Rest of the country | 8.76 | 1,683 |
| offset | 1952–56 | South | −2.82 | 1,414 |
| offset | 1952–56 | Rest of the country | 0.79 | 1,683 |
| spread | 1956–60 | South | 18.23 | 1,417 |
| spread | 1956–60 | Rest of the country | 12.63 | 1,683 |
| offset | 1956–60 | South | −8.70 | 1,417 |
| offset | 1956–60 | Rest of the country | 2.11 | 1,683 |
| spread | 1960–64 | South | 33.49 | 1,415 |
| spread | 1960–64 | Rest of the country | 11.44 | 1,687 |
| offset | 1960–64 | South | −16.52 | 1,415 |
| offset | 1960–64 | Rest of the country | 4.91 | 1,687 |
| spread | 1964–68 | South | 39.16 | 1,419 |
| spread | 1964–68 | Rest of the country | 9.43 | 1,688 |
| offset | 1964–68 | South | 13.63 | 1,419 |
| offset | 1964–68 | Rest of the country | −4.20 | 1,688 |
| spread | 1968–72 | South | 25.37 | 1,422 |
| spread | 1968–72 | Rest of the country | 9.99 | 1,687 |
| offset | 1968–72 | South | −14.73 | 1,422 |
| offset | 1968–72 | Rest of the country | 5.15 | 1,687 |
| spread | 1972–76 | South | 20.70 | 1,422 |
| spread | 1972–76 | Rest of the country | 9.66 | 1,688 |
| offset | 1972–76 | South | 21.93 | 1,422 |
| offset | 1972–76 | Rest of the country | −8.04 | 1,688 |
| spread | 1976–80 | South | 11.08 | 1,425 |
| spread | 1976–80 | Rest of the country | 10.57 | 1,687 |
| offset | 1976–80 | South | −2.92 | 1,425 |
| offset | 1976–80 | Rest of the country | 0.96 | 1,687 |
| spread | 1980–84 | South | 12.04 | 1,425 |
| spread | 1980–84 | Rest of the country | 8.01 | 1,687 |
| offset | 1980–84 | South | −9.28 | 1,425 |
| offset | 1980–84 | Rest of the country | 4.21 | 1,687 |
| spread | 1984–88 | South | 6.97 | 1,425 |
| spread | 1984–88 | Rest of the country | 5.39 | 1,689 |
| offset | 1984–88 | South | −2.43 | 1,425 |
| offset | 1984–88 | Rest of the country | 1.12 | 1,689 |
| spread | 1988–92 | South | 7.65 | 1,425 |
| spread | 1988–92 | Rest of the country | 7.54 | 1,689 |
| offset | 1988–92 | South | 0.91 | 1,425 |
| offset | 1988–92 | Rest of the country | −0.09 | 1,689 |
| spread | 1992–96 | South | 6.66 | 1,424 |
| spread | 1992–96 | Rest of the country | 8.33 | 1,690 |
| offset | 1992–96 | South | −1.24 | 1,424 |
| offset | 1992–96 | Rest of the country | 0.67 | 1,690 |
| spread | 1996–2000 | South | 9.13 | 1,423 |
| spread | 1996–2000 | Rest of the country | 6.92 | 1,690 |
| offset | 1996–2000 | South | −1.98 | 1,423 |
| offset | 1996–2000 | Rest of the country | 1.08 | 1,690 |
| spread | 2000–04 | South | 6.58 | 1,423 |
| spread | 2000–04 | Rest of the country | 5.83 | 1,690 |
| offset | 2000–04 | South | −0.73 | 1,423 |
| offset | 2000–04 | Rest of the country | 0.49 | 1,690 |
| spread | 2004–08 | South | 9.30 | 1,423 |
| spread | 2004–08 | Rest of the country | 6.34 | 1,691 |
| offset | 2004–08 | South | −1.83 | 1,423 |
| offset | 2004–08 | Rest of the country | 1.32 | 1,691 |
| spread | 2008–12 | South | 4.50 | 1,423 |
| spread | 2008–12 | Rest of the country | 5.18 | 1,691 |
| offset | 2008–12 | South | 1.17 | 1,423 |
| offset | 2008–12 | Rest of the country | −0.46 | 1,691 |
| spread | 2012–16 | South | 9.20 | 1,422 |
| spread | 2012–16 | Rest of the country | 11.61 | 1,690 |
| offset | 2012–16 | South | 1.04 | 1,422 |
| offset | 2012–16 | Rest of the country | −0.34 | 1,690 |
| spread | 2016–20 | South | 6.68 | 1,422 |
| spread | 2016–20 | Rest of the country | 5.03 | 1,691 |
| offset | 2016–20 | South | 0.14 | 1,422 |
| offset | 2016–20 | Rest of the country | −0.20 | 1,691 |
| spread | 2020–24 | South | 4.40 | 1,422 |
| spread | 2020–24 | Rest of the country | 4.50 | 1,689 |
| offset | 2020–24 | South | 0.36 | 1,422 |
| offset | 2020–24 | Rest of the country | −0.01 | 1,689 |

Views: Spread within each region (view = spread); South against the nation (series = South, view = offset).

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Note: The South is the Census Bureau's South region: the states from Delaware, Maryland and West Virginia through Texas and Oklahoma, and the District of Columbia, which has returns from 1964. The national swing used in the second view is the one computed on all matched counties.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/south_and_rest.json

### Table 6. County margins correlated with the previous election's margins above 0.9 in 3 of 29 pairs through 1984 and in all 10 pairs since

Vote-weighted correlation between a county's two-party margin and its margin in an earlier election, plotted at the later election

| Elections compared | Compared with | Correlation | Counties |
| --- | --- | ---: | ---: |
| 1868–72 | Previous election | 0.542 | 1,687 |
| 1872–76 | Previous election | 0.646 | 2,151 |
| 1876–80 | Previous election | 0.887 | 2,216 |
| 1880–84 | Previous election | 0.903 | 2,283 |
| 1884–88 | Previous election | 0.911 | 2,345 |
| 1888–92 | Previous election | 0.821 | 2,424 |
| 1892–96 | Previous election | 0.334 | 2,654 |
| 1896–1900 | Previous election | 0.741 | 2,695 |
| 1900–04 | Previous election | 0.863 | 2,680 |
| 1904–08 | Previous election | 0.897 | 2,707 |
| 1908–12 | Previous election | 0.664 | 2,832 |
| 1912–16 | Previous election | 0.590 | 2,942 |
| 1916–20 | Previous election | 0.821 | 3,018 |
| 1920–24 | Previous election | 0.895 | 3,048 |
| 1924–28 | Previous election | 0.527 | 3,083 |
| 1928–32 | Previous election | 0.685 | 3,095 |
| 1932–36 | Previous election | 0.838 | 3,095 |
| 1936–40 | Previous election | 0.887 | 3,094 |
| 1940–44 | Previous election | 0.968 | 3,093 |
| 1944–48 | Previous election | 0.874 | 3,095 |
| 1948–52 | Previous election | 0.842 | 3,094 |
| 1952–56 | Previous election | 0.897 | 3,097 |
| 1956–60 | Previous election | 0.761 | 3,100 |
| 1960–64 | Previous election | 0.514 | 3,102 |
| 1964–68 | Previous election | 0.551 | 3,107 |
| 1968–72 | Previous election | 0.674 | 3,109 |
| 1972–76 | Previous election | 0.510 | 3,110 |
| 1976–80 | Previous election | 0.854 | 3,112 |
| 1980–84 | Previous election | 0.862 | 3,112 |
| 1984–88 | Previous election | 0.959 | 3,114 |
| 1988–92 | Previous election | 0.940 | 3,114 |
| 1992–96 | Previous election | 0.943 | 3,114 |
| 1996–2000 | Previous election | 0.958 | 3,113 |
| 2000–04 | Previous election | 0.975 | 3,113 |
| 2004–08 | Previous election | 0.964 | 3,114 |
| 2008–12 | Previous election | 0.989 | 3,114 |
| 2012–16 | Previous election | 0.958 | 3,112 |
| 2016–20 | Previous election | 0.988 | 3,113 |
| 2020–24 | Previous election | 0.992 | 3,111 |
| 1868–84 | Four elections earlier | 0.673 | 1,688 |
| 1872–88 | Four elections earlier | 0.499 | 2,155 |
| 1876–92 | Four elections earlier | 0.709 | 2,227 |
| 1880–96 | Four elections earlier | 0.593 | 2,287 |
| 1884–1900 | Four elections earlier | 0.756 | 2,336 |
| 1888–1904 | Four elections earlier | 0.784 | 2,398 |
| 1892–1908 | Four elections earlier | 0.555 | 2,642 |
| 1896–1912 | Four elections earlier | 0.533 | 2,693 |
| 1900–16 | Four elections earlier | 0.807 | 2,710 |
| 1904–20 | Four elections earlier | 0.830 | 2,720 |
| 1908–24 | Four elections earlier | 0.860 | 2,850 |
| 1912–28 | Four elections earlier | 0.282 | 2,943 |
| 1916–32 | Four elections earlier | 0.750 | 3,020 |
| 1920–36 | Four elections earlier | 0.524 | 3,052 |
| 1924–40 | Four elections earlier | 0.573 | 3,080 |
| 1928–44 | Four elections earlier | 0.533 | 3,094 |
| 1932–48 | Four elections earlier | 0.733 | 3,095 |
| 1936–52 | Four elections earlier | 0.689 | 3,092 |
| 1940–56 | Four elections earlier | 0.724 | 3,091 |
| 1944–60 | Four elections earlier | 0.588 | 3,092 |
| 1948–64 | Four elections earlier | 0.053 | 3,090 |
| 1952–68 | Four elections earlier | 0.653 | 3,094 |
| 1956–72 | Four elections earlier | 0.233 | 3,095 |
| 1960–76 | Four elections earlier | 0.763 | 3,100 |
| 1964–80 | Four elections earlier | 0.451 | 3,104 |
| 1968–84 | Four elections earlier | 0.724 | 3,108 |
| 1972–88 | Four elections earlier | 0.847 | 3,109 |
| 1976–92 | Four elections earlier | 0.644 | 3,112 |
| 1980–96 | Four elections earlier | 0.721 | 3,111 |
| 1984–2000 | Four elections earlier | 0.828 | 3,112 |
| 1988–2004 | Four elections earlier | 0.810 | 3,111 |
| 1992–2008 | Four elections earlier | 0.796 | 3,112 |
| 1996–2012 | Four elections earlier | 0.842 | 3,112 |
| 2000–16 | Four elections earlier | 0.842 | 3,111 |
| 2004–20 | Four elections earlier | 0.864 | 3,112 |
| 2008–24 | Four elections earlier | 0.900 | 3,112 |

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Note: A county needs returns in both elections to enter a correlation.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/margin_persistence.json

### Table 7. 2020 to 2024 is the lowest pair under all 10 versions of the spread

Spread of county swings for 2020 to 2024 and for the next lowest pair under five measures, each weighted by votes and with each county counted once, percentage points

| Measure | Counted | 2020 to 2024 (points) | Next lowest pair | Its value (points) | Margin (points) |
| --- | --- | ---: | --- | ---: | ---: |
| Standard deviation | Weighted by votes | 4.47 | 2008–12 | 4.97 | 0.51 |
| Standard deviation without small counties | Weighted by votes | 4.47 | 2008–12 | 4.97 | 0.50 |
| Standard deviation on the fixed panel of counties | Weighted by votes | 4.19 | 2008–12 | 5.00 | 0.81 |
| Median absolute deviation, scaled | Weighted by votes | 3.98 | 2008–12 | 4.19 | 0.21 |
| Interquartile range, scaled | Weighted by votes | 3.96 | 2008–12 | 4.27 | 0.31 |
| Standard deviation | Each county counted once | 3.36 | 2016–20 | 5.19 | 1.83 |
| Standard deviation without small counties | Each county counted once | 3.31 | 2016–20 | 5.12 | 1.82 |
| Standard deviation on the fixed panel of counties | Each county counted once | 2.84 | 2016–20 | 4.35 | 1.51 |
| Median absolute deviation, scaled | Each county counted once | 2.74 | 2016–20 | 4.20 | 1.47 |
| Interquartile range, scaled | Each county counted once | 2.76 | 2016–20 | 4.22 | 1.46 |

Note: Full counts of votes: there is no sampling, so the estimates have no confidence interval.

Note: Dropping small counties removes counties with fewer than 1,000 two-party votes in either election of a pair. The fixed panel keeps the 1,652 counties with a positive two-party vote in all 40 elections. The scaled median absolute deviation and the scaled interquartile range are rescaled to equal the standard deviation for a normal distribution.

Source: County presidential returns, 1868-2024 (Algara and Amlani for 1868-2020, MIT Election Data and Science Lab for 2024); full counts, not survey estimates; county swings weighted by two-party votes in the later election unless stated

Data: https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/robustness_versions.json

## All estimates

Every fact in facts.json (98), sorted by id.

| Fact id | Value | Unit | Estimand | Population | Period | Interval | n | Weights | Source | Note |
| --- | ---: | --- | --- | --- | --- | --- | ---: | --- | --- | --- |
| band | 5 | percentage points of the two-party margin | definition of 'near the national swing' | half-width of the band around the national swing | 1868-2024 |   |   | none (full counts) | County election returns |   |
| bin_width | 2 | percentage points of the two-party margin | bin width | width of a bin in the distribution figure | 1868-2024 |   |   | none (full counts) | County election returns |   |
| corr1_1896 | 0.33 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins in the pair's two elections | counties with returns in both elections of the pair, Alaska excluded | 1892 to 1896 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr1_1964 | 0.51 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins in the pair's two elections | counties with returns in both elections of the pair, Alaska excluded | 1960 to 1964 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr1_1976 | 0.51 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins in the pair's two elections | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr1_2012 | 0.99 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins in the pair's two elections | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr1_2016 | 0.96 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins in the pair's two elections | counties with returns in both elections of the pair, Alaska excluded | 2012 to 2016 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr1_latest | 0.99 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins in the pair's two elections | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr4_1988 | 0.85 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins four elections apart | counties with returns in 1972 and 1988 | 1972 to 1988 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr4_latest | 0.90 | correlation coefficient, from −1 to +1 | vote-weighted correlation between county margins four elections apart | counties with returns in 2008 and 2024 | 2008 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| corr_cut | 0.9 | correlation coefficient, from −1 to +1 | threshold on the vote-weighted correlation | threshold for counting pairs | 1868-2024 |   |   | none (full counts) | County election returns |   |
| counties_within_1928 | 8.5% | percent of matched counties | share of counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 1924 to 1928 |   |   | none (full counts) | County election returns |   |
| counties_within_1976 | 21.2% | percent of matched counties | share of counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| counties_within_2012 | 58.8% | percent of matched counties | share of counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 |   |   | none (full counts) | County election returns |   |
| counties_within_latest | 75.6% | percent of matched counties | share of counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| counties_within_mean_latest | 86.3% | percent of matched counties | share of counties within the band of the vote-weighted mean county swing | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| cov_first | 91.7% | percent of the later election's two-party votes | share of two-party votes cast in matched counties | counties with returns in both elections of the pair, Alaska excluded | 1868 to 1872 |   |   | none (full counts) | County election returns |   |
| cov_min | 97.7% | percent of the later election's two-party votes | lowest share of two-party votes cast in matched counties, pairs after 1868 to 1872 | counties with returns in both elections of the pair, Alaska excluded | 1872 to 2024 |   |   | none (full counts) | County election returns |   |
| cut | 10 | standard deviation, percentage points of the two-party margin | threshold on the vote-weighted standard deviation | threshold for counting pairs | 1868-2024 |   |   | none (full counts) | County election returns |   |
| cut_hi | 12 | standard deviation, percentage points of the two-party margin | threshold on the vote-weighted standard deviation | alternative threshold for counting pairs | 1868-2024 |   |   | none (full counts) | County election returns |   |
| cut_lo | 8 | standard deviation, percentage points of the two-party margin | threshold on the vote-weighted standard deviation | alternative threshold for counting pairs | 1868-2024 |   |   | none (full counts) | County election returns |   |
| dist_lim | 60 | percentage points of the two-party margin | half-width of the plotted range | range of the bins in the distribution figure | 1868-2024 |   |   | none (full counts) | County election returns |   |
| jack_gap_max | 0.7 | standard deviation, percentage points of the two-party margin | largest difference between the vote-weighted standard deviations of the two pairs over the leave-one-state-out runs | matched counties with one state or the District of Columbia left out at a time | 2008 to 2012 and 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| jack_gap_min | 0.3 | standard deviation, percentage points of the two-party margin | smallest difference between the vote-weighted standard deviations of the two pairs over the leave-one-state-out runs | matched counties with one state or the District of Columbia left out at a time | 2008 to 2012 and 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| mean_swing_latest | −4.8 | change in the two-party margin, percentage points of the two-party margin | vote-weighted mean of county swings | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| n_corr_early_above | 3 | pairs | count of pairs whose vote-weighted correlation with the previous election exceeds the threshold | pairs ending in 1984 or earlier | 1868 to 1984 |   |   | none (full counts) | County election returns |   |
| n_early | 29 | pairs | count of pairs | pairs ending in 1984 or earlier | 1868 to 1984 |   |   | none (full counts) | County election returns |   |
| n_early_above | 28 | pairs | count of pairs with a vote-weighted standard deviation above the threshold | pairs ending in 1984 or earlier | 1868 to 1984 |   |   | none (full counts) | County election returns |   |
| n_early_above_hi | 22 | pairs | count of pairs with a vote-weighted standard deviation above the alternative threshold | pairs ending in 1984 or earlier | 1868 to 1984 |   |   | none (full counts) | County election returns |   |
| n_early_above_lo | 28 | pairs | count of pairs with a vote-weighted standard deviation above the alternative threshold | pairs ending in 1984 or earlier | 1868 to 1984 |   |   | none (full counts) | County election returns |   |
| n_elections | 40 | presidential elections | count of elections | counties with returns, Alaska excluded | 1868-2024 |   |   | none (full counts) | County election returns |   |
| n_id_1912 | 27 | counties | count of rows dropped before any calculation because no total vote count is reported | Idaho counties in 1912 | 1912 |   |   | none (full counts) | County election returns |   |
| n_late | 10 | pairs | count of pairs | pairs ending in 1988 or later | 1984 to 2024 |   |   | none (full counts) | County election returns |   |
| n_late_below | 9 | pairs | count of pairs with a vote-weighted standard deviation below the threshold | pairs ending in 1988 or later | 1984 to 2024 |   |   | none (full counts) | County election returns |   |
| n_late_below_hi | 10 | pairs | count of pairs with a vote-weighted standard deviation below the alternative threshold | pairs ending in 1988 or later | 1984 to 2024 |   |   | none (full counts) | County election returns |   |
| n_late_below_lo | 9 | pairs | count of pairs with a vote-weighted standard deviation below the alternative threshold | pairs ending in 1988 or later | 1984 to 2024 |   |   | none (full counts) | County election returns |   |
| n_late_rise | 4 | pairs | count of pairs whose vote-weighted standard deviation is higher than the previous pair's | pairs ending in 1988 or later | 1984 to 2024 |   |   | none (full counts) | County election returns |   |
| n_matched_first | 1,687 | counties | count of counties matched on FIPS | counties with returns in both elections of the pair, Alaska excluded | 1868 to 1872 |   |   | none (full counts) | County election returns |   |
| n_matched_latest | 3,111 | counties | count of counties matched on FIPS | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| n_measures | 10 | versions of the spread | count of spread measures (five definitions, vote-weighted and county-equal) | pairs of consecutive presidential elections | 1868-2024 |   |   | none (full counts) | County election returns |   |
| n_no_total | 53 | county rows | count of rows dropped before any calculation | county rows with Democratic and Republican votes and no total vote count | 1868-2024 |   |   | none (full counts) | County election returns |   |
| n_pairs | 39 | pairs of consecutive presidential elections | count of pairs | counties with returns, Alaska excluded | 1868-2024 |   |   | none (full counts) | County election returns |   |
| n_panel | 1,652 | counties | count of counties in the fixed panel | counties with a positive two-party vote in all 40 elections | 1868-2024 |   |   | none (full counts) | County election returns |   |
| n_pre | 18 | pairs | count of pairs | pairs ending in 1940 or earlier | 1868 to 1940 |   |   | none (full counts) | County election returns |   |
| n_rest_wider_pre | 10 | pairs | count of pairs in which the rest of the country's spread exceeds the South's | pairs ending in 1940 or earlier | 1868 to 1940 |   |   | none (full counts) | County election returns |   |
| n_south_run | 13 | pairs | count of consecutive pairs in which the South's spread exceeds the rest of the country's | pairs from 1940 to 1944 through 1988 to 1992 | 1940-1992 |   |   | none (full counts) | County election returns |   |
| n_top10_shaded | 7 | pairs | count of those pairs that are Reconstruction pairs or include a strong third-party election | the ten pairs with the largest vote-weighted standard deviation | 1868-2024 |   |   | none (full counts) | County election returns |   |
| n_u_larger | 35 | pairs | count of pairs where the county-equal standard deviation exceeds the vote-weighted one | pairs of consecutive presidential elections | 1868-2024 |   |   | none (full counts) | County election returns |   |
| naive_wrong_c_1976 | 50.9% | percent of matched counties | share of counties whose two-party winner differs from the earlier election's winner | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| naive_wrong_c_latest | 2.8% | percent of matched counties | share of counties whose two-party winner differs from the earlier election's winner | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| naive_wrong_n_1976 | 1,584 | counties | count of counties whose two-party winner differs from the earlier election's winner | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| naive_wrong_n_latest | 87 | counties | count of counties whose two-party winner differs from the earlier election's winner | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| nat_swing_latest | −6.1 | change in the two-party margin, percentage points of the two-party margin | change in the summed two-party margin of matched counties | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| no_total_max_shift | 0.12 | standard deviation, percentage points of the two-party margin | largest change in any pair's vote-weighted standard deviation when the rows with no total_votes are kept | counties with returns in both elections of the pair, Alaska excluded | 1868-2024 |   |   | none (full counts) | County election returns |   |
| ref_gap_latest | −1.3 | percentage points of the two-party margin | national swing minus the vote-weighted mean of county swings | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| rel_median_latest | +1.8 | percentage points of the two-party margin, relative to the national swing | vote-weighted median of county swings minus the national swing | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| rest_gap_1996 | 1.7 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation within the rest of the country minus that within the South | counties in the Census South region and outside it | 1992 to 1996 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| rest_sd_1964 | 11.4 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties outside the Census South region | 1960 to 1964 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| rest_sd_1976 | 9.7 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties outside the Census South region | 1972 to 1976 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| rest_sd_latest | 4.5 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties outside the Census South region | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| rise_2016 | 5.8 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation in 2012 to 2016 minus that in 2008 to 2012 | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 and 2012 to 2016 |   |   | none (full counts) | County election returns |   |
| robust_gap_min | 0.21 | standard deviation, percentage points of the two-party margin | smallest difference, over the ten versions, between the next lowest pair's value and the 2020 to 2024 value | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 and the next lowest pair |   |   | none (full counts) | County election returns |   |
| sd_u_2020 | 5.2 | standard deviation, percentage points of the two-party margin | county-equal standard deviation of county swings | counties with returns in both elections of the pair, Alaska excluded | 2016 to 2020 |   |   | none (full counts) | County election returns |   |
| sd_u_gap | 1.8 | standard deviation, percentage points of the two-party margin | county-equal standard deviation in 2016 to 2020 minus that in 2020 to 2024 | counties with returns in both elections of the pair, Alaska excluded | 2016 to 2020 and 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| sd_u_latest | 3.4 | standard deviation, percentage points of the two-party margin | county-equal standard deviation of county swings | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| sd_w_1896 | 39.0 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 1892 to 1896 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| sd_w_1944 | 6.4 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 1940 to 1944 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| sd_w_2012 | 5.0 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| sd_w_2016 | 10.8 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 2012 to 2016 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| sd_w_2020 | 5.7 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 2016 to 2020 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| sd_w_gap_latest | 0.5 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation in 2008 to 2012 minus that in 2020 to 2024 | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 and 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| sd_w_late_max | 7.9 | standard deviation, percentage points of the two-party margin | highest vote-weighted standard deviation among the pairs ending in 1988 or later that fall below the threshold | pairs ending in 1988 or later with a standard deviation below the threshold | 1984 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| sd_w_latest | 4.5 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings about their weighted mean | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| small_floor | 1,000 | two-party votes | definition of a small county | floor for the small-county check, applied in both elections of a pair | 1868-2024 |   |   | none (full counts) | County election returns |   |
| south_above_1976 | 93.5% | percent of counties in the Census South region | share of counties that swung 5 or more points more toward the Democrats than the nation | counties in the Census South region | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| south_gap_1988 | 1.6 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation within the South minus that within the rest of the country | counties in the Census South region and outside it | 1984 to 1988 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| south_gap_1992 | 0.1 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation within the South minus that within the rest of the country | counties in the Census South region and outside it | 1988 to 1992 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| south_offset_1976 | +21.9 | change in the two-party margin, percentage points of the two-party margin | region's summed two-party margin swing minus the national swing | counties in the Census South region | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| south_offset_max | 2.4 | percentage points of the two-party margin | largest absolute value of the region's margin swing minus the national swing | counties in the Census South region | 1984 to 2024 |   |   | none (full counts) | County election returns |   |
| south_sd_1964 | 33.5 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties in the Census South region | 1960 to 1964 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| south_sd_1968 | 39.2 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties in the Census South region | 1964 to 1968 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| south_sd_1976 | 20.7 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties in the Census South region | 1972 to 1976 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| south_sd_latest | 4.4 | standard deviation, percentage points of the two-party margin | vote-weighted standard deviation of county swings within the region | counties in the Census South region | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| tail_votes_1896 | 10.0% | percent of the later election's two-party votes | share of votes cast in counties whose relative swing lies beyond the plotted range | counties with returns in both elections of the pair, Alaska excluded | 1892 to 1896 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| third_cut | 10% | percent of all votes cast | cutoff for a strong third-party vote | counties with returns, Alaska excluded | 1868-2024 |   |   | none (full counts) | County election returns |   |
| uniform_cut_1976 | 26% | percent fewer counties called wrong | one minus the count of counties called wrong by the uniform national swing over the count called wrong by keeping the earlier winner | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| uniform_cut_latest | 28% | percent fewer counties called wrong | one minus the count of counties called wrong by the uniform national swing over the count called wrong by keeping the earlier winner | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| uniform_wrong_c_1976 | 37.8% | percent of matched counties | share of counties whose winner differs from the winner predicted by the earlier margin plus the national swing | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts) | County election returns |   |
| uniform_wrong_c_latest | 2.0% | percent of matched counties | share of counties whose winner differs from the winner predicted by the earlier margin plus the national swing | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts) | County election returns |   |
| votes_above_latest | 19.8% | percent of the later election's two-party votes | share of votes cast in counties that swung 5 or more points more toward the Democrats than the nation | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_below_latest | 7.1% | percent of the later election's two-party votes | share of votes cast in counties that swung 5 or more points more toward the Republicans than the nation | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_1896 | 22.7% | percent of the later election's two-party votes | share of votes cast in counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 1892 to 1896 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_1976 | 20.3% | percent of the later election's two-party votes | share of votes cast in counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 1972 to 1976 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_2012 | 73.3% | percent of the later election's two-party votes | share of votes cast in counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 2008 to 2012 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_2016 | 34.0% | percent of the later election's two-party votes | share of votes cast in counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 2012 to 2016 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_early_max | 62.0% | percent of the later election's two-party votes | highest share of votes within the band of the national swing among pairs ending in 1984 or earlier | pairs ending in 1984 or earlier | 1940 to 1944 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_latest | 73.1% | percent of the later election's two-party votes | share of votes cast in counties whose swing is within the band of the national swing | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |
| votes_within_mean_latest | 80.0% | percent of the later election's two-party votes | share of votes cast in counties within the band of the vote-weighted mean county swing | counties with returns in both elections of the pair, Alaska excluded | 2020 to 2024 |   |   | none (full counts); county swings weighted by two-party votes in the later election | County election returns |   |

## Definitions

- Swing: The change in a place's two-party margin between two elections. In this book a positive swing is a move toward the Democrats.
- Standard deviation: A measure of how far values typically fall from their average. A larger standard deviation means the values are more spread out.
- County two-party margin: The Democratic vote minus the Republican vote, divided by the sum of the two, so a positive value is a Democratic lead. Votes for other candidates are left out.
- Percentage point: The unit for the difference between two percentages. A change from one share to another is stated in points, not in percent, so that absolute and relative change are not confused.
- National swing: The change between two elections in the Democratic minus Republican margin for the country as a whole. A county's own swing is compared with it to show whether the county moved with the nation or against it.
- Matched counties: The counties that report a vote in both elections being compared. Changes are computed on them so that a county created, merged or renamed between the two elections does not distort the comparison.
- Ecological inference: Drawing a conclusion about individuals from data on groups or places, such as counties. A pattern across counties can differ from the pattern among the people who live in them.

## Methods

Sample: county presidential returns for the 40 elections from 1868 to 2024 (Algara and Amlani for 1868 to 2020, MIT Election Data and Science Lab for 2024), from the repaired file whose 2024 totals are corrected for 173 counties in South Carolina, Wisconsin and West Virginia.

Rows dropped before any calculation: 41 Alaska rows (Alaska reports election districts and has no returns before 2024), 50 rows with no FIPS code (defunct counties), 88 rows with no vote count, 53 more rows with Democratic and Republican votes but no total vote count (27 of them Idaho counties in 1912, so Idaho has no county in the pairs 1908 to 1912 and 1912 to 1916; keeping these rows changes no pair's vote-weighted standard deviation by more than 0.12 points and leaves 2020 to 2024 the lowest pair) and 74 rows with no two-party votes. Coverage shares are computed on the rows kept.

Pairs: each pair of consecutive elections uses the counties present in both, matched on FIPS code, so a pair holds 1,687 to 3,114 counties; county boundaries are not harmonized.

Estimand: the two-party margin is 100 times the Democratic minus the Republican votes over their sum; a county's swing is its margin in the later election minus its margin in the earlier one; the national swing is the same change in the summed margin of the matched counties; the relative swing is the county swing minus the national swing.

Spread: the standard deviation of county swings about their own mean, population divisor, weighted by two-party votes in the later election (county-equal in one view).

Share near the national swing: the absolute difference from the reference is below 5 points, counted by votes and by counties, against the national swing and against the vote-weighted mean county swing.

Robustness: counties with fewer than 1,000 two-party votes in either election dropped; a fixed panel of 1,652 counties with a positive two-party vote in all 40 elections; the median absolute deviation (multiplied by 1.4826) and the interquartile range (divided by 1.349), each weighted by two-party votes (a weighted quantile is the first value whose cumulative weight reaches the quantile) and county-equal (the sample median, and linear interpolation between order statistics for the quartiles); the vote-weighted standard deviation recomputed for every pair with one state or the District of Columbia left out at a time.

Uniform-swing test: a county is called wrong when the sign of its earlier margin plus the national swing differs from the sign of its later margin.

Persistence: Pearson correlation of the county margin with the margin one and four elections earlier, weighted by two-party votes in the later election.

Regions: the Census South (AL, AR, DE, DC, FL, GA, KY, LA, MD, MS, NC, OK, SC, TN, TX, VA, WV) against all other states.

Weights: none from a survey, because the returns are full counts. Interval method: none; a full count has no sampling error, so no confidence interval is reported, and differences between measures come from definitions and the county set, not from chance. Suppression: none for the county series; a regional figure needs at least 30 matched counties in the region, and every pair meets that.

## What these data cannot show

- County returns describe places, not voters.
- A county that swings with the nation can contain groups that moved in opposite directions, and returns cannot separate voters who changed their choice from people who started or stopped voting or moved in or out, a limit known as ecological inference.
- The national swing has a related limit.
- It is a change in a summed margin, so it counts where votes were cast as well as how counties voted, and in 2020 to 2024 it differed from the mean county swing by −1.3 points.
- The returns are full counts, so the figures carry no sampling intervals, and differences between measures come from how they are defined and which counties enter.
- The county set is one of those choices.
- Counties are matched on FIPS code and boundaries are not harmonized, so a county that gained or lost territory is treated as one unit, and the county-equal figures depend on how many small counties exist.
- The 53 county rows that have Democratic and Republican votes but no total vote count are left out, among them 27 Idaho counties in 1912, and keeping them changes no pair's spread by more than 0.12 points.
- Returns before 1965 count the votes of the people allowed to vote.
- In much of the South, barriers to voting kept many Black citizens from the ballot until the Voting Rights Act, so early margins describe smaller electorates than the populations of those counties.
- The two-party margin also leaves out third-party votes, which is why the shaded pairs in Table 1 are the least comparable with the rest.
- The chapter measures how uniformly counties moved and does not say why.
- How much of the county vote census characteristics account for is the subject of Chapter 12.1, Five axes of the county vote (https://vishalsingh.org/politics/five-axes-of-the-county-vote), and ticket splitting is taken up in Chapter 10.3, Down the ballot (https://vishalsingh.org/politics/down-the-ballot).
- Chapter 10.4, The Electoral College (https://vishalsingh.org/politics/the-electoral-college; planned) turns state margins into electoral outcomes, and Chapter 15.1, Party and place (https://vishalsingh.org/politics/party-and-place) compares how far partisans' issue positions differ between deep-red and deep-blue counties with the gap between the parties.
- The series also makes no forecast.
- The spread was 5.0 points in 2008 to 2012 and 10.8 in 2012 to 2016.

## References

1. Amlani, Sharif; Algara, Carlos (2021). Partisanship & Nationalization in American Elections: Evidence from Presidential, Senatorial, & Gubernatorial Elections in the U.S. Counties, 1872-2020. Electoral Studies 73: 102387. https://doi.org/10.1016/j.electstud.2021.102387
2. Stokes, Donald E. (1967). Parties and the Nationalization of Electoral Forces. In William Nisbet Chambers and Walter Dean Burnham (eds.), The American Party Systems: Stages of Political Development, pp. 182-202. New York: Oxford University Press.
3. Bartels, Larry M. (1998). Electoral Continuity and Change, 1868-1996. Electoral Studies 17(3): 301-326. https://doi.org/10.1016/S0261-3794(98)00035-3
4. Claggett, William; Flanigan, William; Zingale, Nancy (1984). Nationalization of the American Electorate. American Political Science Review 78(1): 77-91. https://doi.org/10.2307/1961250
5. Caramani, Daniele (2004). The Nationalization of Politics: The Formation of National Electorates and Party Systems in Western Europe. Cambridge University Press.
6. Hopkins, Daniel J. (2018). The Increasingly United States: How and Why American Political Behavior Nationalized. University of Chicago Press.

## Provenance

- Pipeline version: 1.0.0
- Build script: book3/chapters/nationalization-of-the-county-vote/build.py (sha256 9b929588166924eec941d9a710fb7429c5e44c4d62556d809ee59c39d944d863)
- Built on: 2026-09-30
- Site commit: 70da8d22fae66721148b0b2ade831dda2a1ebdd8

Inputs:

| File | Size (bytes) | SHA-256, first 1 MB | SHA-256, last 1 MB |
| --- | ---: | --- | --- |
| data/county/pres_county_1868_2024.parquet | 6,295,675 | bec11c7a0cb5d4180bbd6809d048bc892dd00dfcdde527fa4da871b1dd3f835f | b2a4f000f2eea72d09af8939555289e924875cca40cd95ec8869104cd575bed7 |

Outputs:

| File | SHA-256 |
| --- | --- |
| facts.json | 6381c8032eba068d911ea297533463f34fb33e5c4a82a0b68bd4e64cf816608e |
| figures/dispersion_series.json | 440ee06fedbf1d9cfdb65ef083daa526c677c3bec2dabe3c09eaa33b3e7a84c2 |
| figures/margin_persistence.json | d0f93f83fc6a88eb4a5575d3716d4521222022270f1f8bb3d293c51283bf6efd |
| figures/robustness_versions.json | 4b5852b84bf5e930c3ff336c65ae1273c3f56a4d4e7ecac2a399a9f79945ade1 |
| figures/share_near_national_swing.json | 32a963f65e3f2fbbab4371001ff93072b2b24b801811326e749bc5a7af8fb585 |
| figures/south_and_rest.json | 71f17da7e36cdbf74c4030307b7c6f8f01fd20acdc4dd70f4f585e8421ba9b24 |
| figures/swing_distribution.json | ee6364344e1ed5b7021922e0c47a84b2e4176ca7e98554e7633c82c1f18250ce |
| figures/swing_map.json | 31dec551a60bcf9ca16d581c0367c4913af50f1ad9886af169cece7c37d945ec |
| meta.json | 4494b84eb22a63e289eeb190f953920244b9a69cdbf0d740a0d42b6a1fb3fe78 |
| public/data/nationalization-of-the-county-vote/swing_map.json | 508df5251e39fe2340235548a78786d05325902cc2b871e5d3a32e3fb19b90ba |
| refs.json | 2f086df86ac5088d4430b2d860047987e091b111bf437d1a492f9c336a8d2ef0 |

## Machine formats

- Report (HTML): https://vishalsingh.org/politics/nationalization-of-the-county-vote/report
- Report (Markdown): https://vishalsingh.org/politics/nationalization-of-the-county-vote/report.md
- Every estimate (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/facts.json
- Table 1, figure "dispersion_series" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/dispersion_series.json
- Table 2, figure "swing_distribution" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/swing_distribution.json
- Table 3, figure "swing_map" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/swing_map.json
- Table 4, figure "share_near_national_swing" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/share_near_national_swing.json
- Table 5, figure "south_and_rest" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/south_and_rest.json
- Table 6, figure "margin_persistence" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/margin_persistence.json
- Table 7, figure "robustness_versions" (JSON): https://vishalsingh.org/politics/report/nationalization-of-the-county-vote/figures/robustness_versions.json
- Payload of "swing_map" (JSON): https://vishalsingh.org/politics/data/nationalization-of-the-county-vote/swing_map.json
- Index of every report: https://vishalsingh.org/politics/llms.txt; all reports in one file: https://vishalsingh.org/politics/llms-full.txt