The NY Times has posted this analysis of mail-in voting in the recent Wisconsin primary, showing that the liberal candidate for the state supreme court (favored by Democrats) did better than the conservative candidate (favored by Republicans). This is no surprise. As I wrote recently in the NY Daily News, the Republican legislature’s failure to move the primary date or ease vote by mail restrictions backfired on Republicans, by both firing up Democrats to vote and by deterring voting by reliable Republican voters. I would not draw a general conclusion, as this article does, that this single election under these conditions “upends” the conventional thinking that vote by mail does not favor one party over another.

From the NYT article:

Barry Burden, a professor of political science at the University of Wisconsin-Madison who is among the academics who have produced studies that found no partisan advantage to mail voting, said the Times analysis of the Wisconsin data did not align with any previous studies from states such as Colorado and Utah, which transitioned to fully vote-by-mail systems in recent years.

“I’m surprised by the results,” Mr. Burden said when told of the gap between in-person and mail results. “It is convincing and surprising that Karofsky appears to have done better among mail voters than in-person voters. That’s a change from past trends. It’s unclear if that’s going to be a permanent change or something very specific to this particular election.”