Swing states
Swing states are those considered to play a key role in the outcome of presidential elections and where both Democratic and Republican parties have similar levels of support. In 2024, there were seven: Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania and Wisconsin. These states control a total of 93 electoral votes, or over a third of the 270 needed to win the electoral college (and the presidentship).
A Clean Sweep
Trump was the first presidential candidate of either party to win all swing states in the past four decades, since Ronald Reagan’s 1984 re-election landslide victory against Walter Mondale, in which he won 49 states.
For comparison, Biden won six of seven swing states in 2020, winning all except North Carolina. While sweeping all swing states isn't an impossible feat, it is one rare enough to remark on.
Among five of the tightest elections since 2000, Trump won the seven closest states in 2024 by particularly wide margins
Trump’s margins of victory in those seven states were wider — easily — than the margins of the seven closest states in the 2020 Trump-Biden election, and every close presidential contest this century. Harris fared worse in these states than Biden did four years earlier.
Trump’s collective margin in these seven battleground states was about 760k. By comparison, the 2000 election (Bush vs. Gore) had collective margins of about 46k in the seven closest states, or about one-sixteenth as much as in 2024.
Down-Ballot Differences
Of the seven swing states, five also held Senate races and one had a gubernatorial contest. Though Trump took all swing states and the Republican candidate won Pennsylvania’s Senate race, the Democrat won the Senate races in Arizona, Michigan, Nevada and Wisconsin, and the gubernatorial contest in North Carolina.
(In North Carolina, Democrats also won the races for lieutenant governor, attorney general, secretary of state, superintendent of public instruction and were narrowly leading in a state Supreme Court race.)
Drop-Off Rates
"Drop-off votes" are the difference between the votes for the President and the next down-ballot race.
In 2024, there were often many more votes for the Republican presidential candidate (Trump) than for the Republican Senate candidate (or major down-ballot race), but not on the Democratic side, especially for swing states.
This is true for percentages as well. The drop-off for Republicans is very high, averaging close to 10% in some swing states (i.e. close to 10% of Republican Presidential voters did not vote for a Republican Senate candidate).
On the Democratic side, the opposite occurs. There are a large number of votes for the Democratic Senate candidate (or major down-ballot race) where there is no vote for the Democratic presidential candidate (Harris).
Compared to Republican candidates, the Democratic drop-off is low and even negative in most states. In Arizona, North Carolina and Ohio, the Democratic drop-off is -5%, or lower (i.e. 5% or more of democratic-leaning voters voted for the Democratic Senate candidate but not the Democratic presidential candidate).
What's weird
A negative drop should normally represent people not comfortable with their party's presidential candidate, but will make up in their conscience by voting their party in the down-ballot. In the context of Trump and Harris, we would expect the negative drop-off to exist on the Republican side, not the Democrat side.
President-Senate Margins
Looking at party president-senate differences again, there are interesting trends in the spread in counties within parties (how clustered the red and blue dots are) and gap between party ticket differences (space between red and blue dots).
What's weird
The spread across counties is abnormally small for swing states. In previous years and non-swing states, counties are fairly spread and randomly clustered with a few outliers, while in 2024 swing state counties turn into almost a single dot. This stands out especially in North Carolina, where all 100 counties show a president-senate difference between 0-5%.
Increased vote-splitting. It's common enough for all counties to split their votes, but it's been getting rarer over the past few decades for all states as the country grows more polarized. Party tickets in 2012-2020 get closer in the middle, then show a small gap between parties in 2024.
President-Senate Historical Differences
How to read these charts
Red = Republican, Blue = Democrat
Each dot is a county, each line is an election year
Positive dot (above the line) = county voted more for the presidential than the senate candidate
Negative dot (below the line) = county voted more for the senate than the presidential candidate
Non-swing states
Swing states