The result: We now see a massive partisan difference – who voters will support for president – when we tabulate by how they want to cast their ballots. YouGov’s most recent surveys conducted for Yahoo News in late June and July show that those who want to vote by mail prefer Joe Biden over Trump by a whopping 70 to 14 percent margin, while those who prefer to vote in person prefer Trump by better than two to one, 59 to 28 percent.

The share that wants to vote by mail is not small. The same two surveys, conducted between June 29 and July 14, find nearly half (45%) of registered voters nationwide say they would prefer to vote by mail, rather than in person. If translated into actual voting behavior, that preference would represent more than double the rate that actually voted by mail in 2016 (21%).

And again, thanks to the aggressive push-back against mail voting by President Trump and his allies, preference for type of voting differs greatly by party identification. By a 75-to–25 percent margin, Republicans (including leaners) prefer to vote by in-person, while a slightly less lopsided 65-to–35 percent margin of Democrats (including leaners) prefers to vote by mail. Non-leaning independents are more divided but narrowly prefer to vote by mail (54% to 46%).