With four days to go until the 2024 general election, more than 66 million votes have already been cast through early mail-in or in-person voting. Political science professor Michael McDonald is tracking these early voting trends at the University of Florida’s Election Lab, and he joined ForbesMaggie McGrath spoke Friday about what the numbers mean for overall turnout figures — and for the two presidential candidates.

“We will have about 160 million people voting,” McDonald said. “The turnout rate will be slightly lower than what we had in the 2020 election.”

The 2020 election marked the highest turnout for a presidential election since 1900, so McDonald warns that’s a high bar to meet. But more interesting than the overall early voting numbers, he says, are the trends within the demographics of early voters this cycle.

“Republicans took action as soon as the in-person early voting period began. Even in 2020 or 2022, Republicans might have voted early in person, but they would wait much later, and they would vote late in the in-person voting period or on Election Day,” McDonald explained. “This time there is a real surge of Republicans voting early in person. And that is very unusual. We have never seen anything like this in the data before.”

Democrats, he said, show a different pattern. During the pandemic, more registered Democrats voted early on the first day of early voting. This year, however, “the Democrats are actually running a deficit. And only in the second week, the third week of in-person early voting, are the Democrats above their 2020 levels. So it almost looks like the Republicans, very energized, came out very quickly to vote.”

Watch the full interview above for more information about who will vote and what this means for the election results.