Yet surprisingly, expanding voting options to make it more convenient hasn’t seemed to have a huge effect on turnout or electoral outcomes. That’s the finding of decades of political science research on advance, early and absentee voting. One prominent study even found that early voting decreases turnout, though that’s a bit of an outlier.
There’s essentially no evidence that the vast expansion of no-excuse absentee mail voting, in which anyone can apply for a mail absentee ballot, had any discernible effect on turnout in 2020. That shouldn’t be a huge surprise: Even universal vote by mail, in which every registered voter is automatically sent a mail ballot (as opposed to every voter having an opportunity to apply for one), increases turnout by only about 2 percent with no discernible partisan advantage.
Believe it or not, turnout increased just as much in the states that didn’t have no-excuse absentee voting as it did in the states that added it for the first time. Similarly, Joe Biden improved over Hillary Clinton’s performance by three percentage points in the states that added it, compared with 2.9 points in the states that did not.