538's Swing-O-Matic interactive shows what could happen in the 2024 election if Harris or Trump gain ground with different demographic groups — and if turnout shifts among others. To build it, we used data from the U.S. Census Bureau and several pollsters to estimate turnout and vote choice in the 2020 election sorted by five key demographic traits: age, education, sex, income and race. The starting map reflects vote preference and turnout levels from 2020's matchup between Trump and President Joe Biden, adjusted for demographic shifts since then.

Use the buttons below, or scroll down the page, to explore how hypothetical changes in vote choice and turnout among different groups could alter the outcome of the 2024 election. To get you started, we've laid out some potential scenarios of demographic swings and their outcomes, such as a potential Trump victory from non-college-educated voters and nonwhite voters shifting right:

Conversely, a potential Harris win might stem in part from older voters and white voters moving to the left:

So while we're waiting on election results, go ahead and click "Explore on your own" to create your own election scenario and play around with the electorate to your heart's content!

Trump and Harris get most of the attention, but today is also a big day for JD Vance and Tim Walz, who will find out if they will become the 50th vice president of the United States. Just as they are on the presidential candidates, Americans are pretty divided in their opinions of the VP aspirants, but one is narrowly above water with the American people and the other is not.

According to 538's averages, 41% of Americans have a favorable opinion of Walz, while only 39% have an unfavorable opinion of him. By contrast, only 38% of Americans have a favorable opinion of Vance, while 45% have an unfavorable one.

With the resurfacing of some of his old comments (like calling liberals "childless cat ladies"), Vance made a bad first impression with the public, and his image never really recovered. However, Republicans can take solace in the fact that vice presidential candidates rarely affect the outcome of the election. Virtually everyone makes their decision based on the names at the top of the ticket, not the bottom.

As I mentioned earlier on the blog, women make up 41% of Democrats' members of Congress, but just 15% of Republicans' members of Congress. That gap is unlikely to shrink after all the races today are projected, because the GOP nominated fewer women to run this cycle, compared to the last two cycles, and only a handful were nominated to run in safe districts.

While there are a number of incumbent female Republicans in Congress almost certain to retain their seats today, []() of GOP primary races, there will likely only be two new faces among the ranks of GOP women in the chambers. That's because non-incumbent female nominees were very uncommon in competitive or safely Republican seats this year. There are only two non-incumbent women running in districts rated as Solid Republican in 538's latest forecast: Julie Fedorchak in North Dakota and Sheri Biggs in South Carolina, who are both shoo-ins for open seats currently held by Republican men.

There are seven other non-incumbent Republican women we will be watching tonight, but they are running in races that our forecast rate as "Likely Democratic" Of these, only two are in open races, while the rest are challenging Democratic incumbents: Kari Lake, who is running in the open Arizona Senate race and wins just 22-in-100 simulations in our forecast against Ruben Gallegos, and Caroleene Dobson, who wins just 9-in-100 simulations against Shomari Figures.

We will be watching these races, and a handful of others where Republican women could win, today:

From taxes to abortion, from immigration to health care, the policy stakes for this presidential election are large. But there is a consolation prize that is likely to go to the party that loses this presidential election: control of the House of Representatives in two years' time.

Political scientists have documented that American electoral politics is subject to powerful, often predictable tides. And as I wrote back in 2016, midterm elections, and especially midterm elections for the U.S. House, offer a clear example of that. Particularly in an era of close margins in the House, whichever party loses the presidency today will become the immediate favorite to retake the House in the next election.

Dating all the way back to 1980, there has only been one presidential election in which the losing party didn't wind up in control of the House of Representatives after the subsequent midterm, regardless of whether they controlled the House at the start of their president's term. In the other 11 elections since then, the party that lost the White House either regained the House or held control in the subsequent midterm. Democratic Presidents Bill Clinton, Barack Obama and Joe Biden all saw their party lose control of the House in their first midterm election; Republican Donald Trump did in 2018 as well.

The only exception came in 2002, when 9/11 had reshaped the political landscape and helped Republicans gain seats in the House while George W. Bush was president. But even Bush was not immune from this pattern — in 2006, two years after his reelection, his Republicans lost control of both the House and the Senate.