What weeks of early-voting data tell us about how Democrats and Republicans are turning out in 2024

Early voting is getting underway throughout the country, including in key battleground states like Georgia, where more than 300,000 people voted Tuesday, the first day of early voting. 

While Virginia isn’t a core battleground state this year, it does have more than two weeks of mail-in and early in-person voting already in the books, including hundreds of thousands of absentee ballots already cast. We closely monitor early-voting trends to set expectations for election night outcomes, and in Virginia a clear pattern has emerged that could be part of a national trend.

So-called consistent voters — those people who regularly show up to vote in most elections — have already made substantial use of early in-person voting in Virginia, particularly in the areas that tend to support Republican candidates. As several other states start early voting, we will be closely watching to see if similar patterns hold elsewhere, because early voting has important implications for how election results might unfold on election night.

Virginia’s first two weeks of voting by mail and early in-person voting suggest that the gap between the early vote in Republican and Democratic counties might be smaller in 2024 compared to 2020.

The table above shows how many votes and absentee ballots were cast in 2020 based on a jurisdiction’s overall lean toward Democratic or Republican candidates. In 2020, about 2.8 million, or 63%, of the roughly 4.5 million total votes in Virginia were cast before Election Day. However, there were substantial differences in the number of early voters based on a city or county’s partisan lean. In those cities and counties that strongly favor Democratic candidates, 70% of voters cast absentee ballots. In comparison, only about 50% of voters in Republican-leaning counties and cities cast absentee ballots.

The table below compares how many 2024 absentee ballots were recorded as returned by Oct. 11 in these same areas, according to TargetSmart, a voter data vendor. So far in 2024, more absentee voting has occurred in places that tend to support Republicans than places that tend to lean Democratic.

One way to capture this trend is by calculating the percentage of 2020 votes in an area that have already been cast in 2024 via absentee ballots. This ranges from about 12% in the areas that are most supportive of Democrats to almost 22% in those areas that lean toward Republicans. 

TargetSmart also provides information on how frequently these voters participated in the past three statewide general elections (the 2020 presidential election, the 2021 gubernatorial election and the 2022 midterm election).

Voters who have participated in most or all of these elections are almost certain to vote in the upcoming presidential election — which means that observing that these voters are casting their ballots well before Election Day instead of later does not tell us much about what the turnout will look like. However, if early voters are less consistent or new voters, it could signal a shift in electoral trends ahead of  November.

So far, it appears that about 90% of the people who have voted in Virginia are consistent voters who participated in at least two or three of these elections. And there are no meaningful differences in the share of consistent voters based on the partisan lean of the area.

While it might be tempting to interpret these patterns as evidence that consistent Democratic voters are going to cast ballots at lower rates than Republicans in Virginia, we assess that such a conclusion is premature. To see why, the table below uses data from the Virginia Public Access Project to show when voters cast absentee ballots in the state’s 2022 election.

Specifically, the table shows what share of the total absentee ballots cast were recorded 25 days before the election. The data shows that only about 21% of the early in-person ballots and 39% of the mail ballots had been cast at this point in 2022. Notably, a higher percentage of the absentee ballots had been cast in areas more supportive of Republicans than in areas more supportive of Democrats.

Why might voters in more Democratic-leaning areas cast their votes later than in areas more supportive of Republicans? One possible explanation is the availability of  “satellite voting locations” in some Virginia jurisdictions. These are additional locations, beyond the general registrar’s office of a county or city, where voters can cast early in-person ballots starting later in October. These satellite voting locations may make early in-person voting accessible in more populous areas, which tend to be more Democratic-leaning. We will be watching closely to see whether these differences by area even out, or possibly reverse, over the next couple of weeks as satellite voting begins.

If we continue to observe turnout lagging in Democratic areas relative to Republican areas after satellite voting begins, this would lead us to do more investigation about whether consistent Democratic voters appear to be less mobilized than normal this election cycle.

Why these patterns matter for the NBC News Decision Desk

Part of why the NBC News Decision Desk watches absentee voting so closely is because of its implications for the sequencing of how votes get reported on election night. The fact that Democrats were more likely to cast mail and early in-person ballots than Republicans made our work on the Decision Desk more challenging than normal in 2020.

We are accustomed to the fact that counties report election results at different speeds on election night. In some states, smaller, largely rural counties tend to report their votes first, while in others larger, mostly urban counties are the first to report. We have long used models that attempt to account for this unevenness by analyzing whether the counties that have reported more votes tend to lean more Democratic or Republican in past elections compared to counties that have reported fewer votes. These models help us assess what the current reported results suggest about the likely final outcomes.

Prior to 2020, these models did not adequately account for the fact that counties also do not report different results by vote mode at the same speed. In some states, counties initially report the mail and early in-person votes, and then the Election Day votes. In others, this order is flipped.

As it became clear in 2020 that Democrats were going to disproportionately vote by mail or early in-person and Republicans were going to disproportionately vote on Election Day, we had to quickly improve our models to not only account for differences in the rates of reporting over counties, but also for differences in which vote modes had been counted. And while we are now in a better place to deal with this issue, it will still generally take us longer to project races in states where there are substantial partisan differences in voters’ use of mail and early in-person voting and differences in the speed of reporting by vote mode.

However, seeing these data out of Virginia make us cautiously optimistic that we may observe less partisan differences by vote mode in 2024 than in 2020, at least in states like Virginia that have extensive early in-person voting.

This story first appeared on NBCNews.com. More from NBC News:

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