A new analysis of early voting data from our US partner network NBC has revealed some interesting and potentially crucial trends in two key states.

According to the numbers, there are signs of an influx of new Democratic voters in Pennsylvania and new Republican voters in Arizona.

Early votes from new voters (voters who did not show up to the polls in 2020) are of particular interest because they are votes that could change what happens in 2024 relative to the last presidential election.

Also important are those who voted in 2020 and do not do so this time, but it is impossible to know before Election Day.

The number of new voters in many of the seven closest states already exceeds the 2020 margin between Joe Biden and Donald Trump. In Pennsylvania, for example, Biden defeated Trump in 2020 by 80,555 votes. This year, more than 100,000 new voters have already cast their ballots in Pennsylvania, with more to come.

While we can’t know how these new voters voted, looking at who they are can provide clues about how 2024 might vary relative to 2020.

Party registration does not perfectly predict a voter’s choice, but new voters who choose to register as Democrats are more likely to vote for Kamala Harris than not, and new voters who register as Republicans are more likely to vote for Trump.

As a result, in swing states where voters can formally register for a party (Arizona, Nevada, North Carolina and Pennsylvania), new party-affiliated voters may provide some clues about the 2024 elections.

Pennsylvania is the closest state according to polls, and the number of new voters who have voted there has already surpassed the 2020 margin.

If everyone from 2020 voted for the same candidate again, these new voters would decide the race.

Pennsylvania

Data from Pennsylvania shows large differences in the number of votes cast by new voters, both by party registration and gender. There are more new voters registered as Democrats than Republicans, and new female voters are driving this partisan divide.

New male voters are only slightly more likely to be Democrats than Republicans, but among new female voters, Democrats outnumber Republicans nearly 2 to 1.

Arizona

As for Arizona, the opposite pattern emerges. While there are fewer new voters than in Pennsylvania (in part because early voting in Arizona started later), the 2020 margin in Arizona was also much smaller: just 10,457 votes.

The number of new voters (86,231 as of Tuesday) is already more than eight times the 2020 Biden-Trump margin in Arizona. And so far the largest proportion of that group of new voters in Arizona are male Republicans.

New voters are also slightly more likely to be registered Republicans than Democrats in the state, unlike in Pennsylvania. But the Republican advantage among new Arizona voters so far is largely being driven by male voters.

Arizona has 11 electoral college votes, while Pennsylvania has 19.

Most analysts have suggested that whoever wins Pennsylvania is much more likely to win the election overall.