For instance, Republican respondents told ABC News/The Washington Post that they preferred to vote in person, 79 percent to 20 percent. But Democratic respondents preferred to vote by mail, 51 percent to 46 percent. That could mean that votes cast in person will skew toward Republicans this fall, while mail-in votes skew toward Democrats. And since in-person votes are typically reported first on election night, that could mean that initial results on Nov. 3 will be overly favorable to Trump — perhaps causing him to claim victory prematurely. But Biden could actually turn out to be the winner days after Election Day in this scenario, as mailed ballots are counted and Democratic votes are added to the till. This could cause a national crisis if Trump decries those late-counted ballots as fraudulent or if he refuses to concede.

In addition, the poll found that college-educated and wealthier voters were more comfortable voting by mail. Specifically, respondents with postgraduate degrees said they preferred voting by mail 54 percent to 44 percent; those with just a four-year college degree were split 49 percent to 49 percent. Respondents with less than four years of college said they preferred to vote in person, 59 percent to 37 percent, and respondents with a high school diploma or less opted for in-person voting 68 percent to 29 percent. As a result, underprivileged voters could be disproportionately affected if the pandemic forces the closure or consolidation of polling places this November, either putting them at heightened risk of contracting COVID-19 while waiting in line or disenfranchising them altogether.