The issue is that we really don’t know the extent to which the early vote will be more Democratic-leaning than the overall tally. There’s no history of early voting during a pandemic. Moreover, just because we know the party affiliation of the voters returning ballots in some states doesn’t mean we know they’re voting for.
And remember, a vote cast on Election Day is worth the exact same as a vote cast early.
Democrats learned that the hard way back in 2016. In a year in which the partisan split between early and Election Day voters was much smaller, Hillary Clinton won voters who cast their ballots before Election Day in two pivotal battlegrounds: Florida and North Carolina.
I can recall a lot of Democrats were giddy that more registered Democrats had voted early in Florida.
But it was Trump who won overwhelmingly with Election Day voters and carried both states.