Four days before the 2024 general election, more than 66 million votes have already been cast by mail or in person. Political science professor Michael McDonald has joined the University of Florida's Election Lab to track these early voting trends Forbes' Maggie McGrath spoke Friday about what the numbers mean for voter turnout overall — and for the two presidential candidates.

“We’re going to get about 160 million people voting,” McDonald said. “Voter turnout will be only slightly lower than in the 2020 election.”

The 2020 election marked the highest voter turnout in a presidential election since 1900, which is why McDonald warns that this is a high bar. But more interesting than the total number of early voters, he said, are the trends in early voter demographics this cycle.

“Republicans showed up in large numbers as soon as the early in-person voting period began. Even in 2020 or 2022, Republicans might have voted in person earlier, but they would wait much later and vote either late in the in-person early voting period or on Election Day,” McDonald explained. “This time there is really a surge in Republicans voting early in person. And that is very unusual. We’ve never seen anything like this in the data.”

Democrats, he said, showed a different pattern. During the pandemic, more registered Democrats voted on the first day early voting was available. This year, however, “Democrats are actually operating at a deficit. And it's only in the second or third week of in-person early voting that Democrats are ahead of their 2020 levels. So it almost looks like Republicans, full of energy, went to the polls very quickly.”

To learn more about who is voting and what it means for election results, watch the full interview above.