More than 57 million Americans have already voted, suggesting a huge voter turnout for 2020. But it's not clear who that would favor.

• More than 57 million Americans have already voted as of Sunday, according to the US Elections Project.
• The Florida professor who runs the US Elections Project said it suggests a total turnout of 65%, which would be the highest since 1908.
• Of those to vote early, almost twice as many are registered Democrats than Republicans, per the states which provide such data.
• However, an increased turnout does not automatically favor one candidate.

More than 57 million Americans have already voted with more than a week to go.

The data comes from the US Elections Project which is run by Dr. Michael P. McDonald, a political science professor at the University of Florida.

It says that the number of votes cast already is already 41.7% of the total votes cast in 2016.

According to the Guardian, McDonald projects from those numbers that the total turnout in 2020 will be 65%. That level of participation would be the highest since 1908.

However — what a surge in turnout could mean for the end result is not obvious.

In a recent analysis, McDonald argued that the early voting trends favor Democratic nominee Joe Biden, because his campaign can stop spending resources on supporters who already turn out, and focus on those who are yet to vote.

The Trump campaign, he argued, is at a disadvantage because it still has many more potential voters to absorb its attention.

However, it is impossible to know how meaningful that difference will prove. Past analyses of the impact of increased turnout suggested that it could go either way.

New York Magazine this week suggested that increased turnout would likely strongly favor Biden it it helps younger voters get to the polls.

Citing a new poll from Axios and SurveyMonkey-Tableau, it noted that voters under 35 in all but five states — and every swing state — favor Biden over Trump.

However, the New York Times earlier this year noted that white working-class supporters — most of whom favor Trump — have also historically not voted in high numbers.

If more of those voters make it to the polls — especially in target areas like Pennsylvania — it could help the Republicans most.