As Trump Sows Doubts on Mail, Democrats Push More In-Person Voting

“There are just some people who want to see their ballot go into the machine,” she said. “We’re just making people aware of all of their options. We want people to feel comfortable putting ballots in the mail, but you can be sure if you drop it off in the drop box.”

William Velchoff of Georgetown, Texas, was among the Democrats who said they planned to vote in person.

“I think Trump and the Republicans in general are trying to screw up mail-in voting,” said Mr. Velchoff, a retired manufacturing engineer who worked in the oil industry. “They’ve given every indication that they’re going to do what they can to throw out mail-in votes.”

The debate over how much to shift away from mail voting comes as Philadelphia Democrats are planning to resume in-person campaigning this weekend, though still safely and socially distanced, after months of digital outreach and phone banking to stay safe during the pandemic. On Thursday, the Biden campaign said it would begin door-to-door canvassing in battleground states.

For some Democratic officials, the push on mail voting is a way to increase their success in the margins, where close states are likely to be decided. Ben Bright, the chairman of the Democratic Party of Washington County, Pa., said he encouraged “low-propensity voters” — those who don’t regularly cast a ballot — to vote by mail. But for “super-voters,” or those who participate in every election, he advised voting in person. That way they will avoid any mistakes that can cause an absentee ballot to be rejected.

“Our thought has always been that if we get 1,000 Democrats to vote by mail that wouldn’t have voted otherwise, and we lose 10 percent due to mistakes, we still gained 900 votes,” Mr. Bright said. “But if 1,000 super-voters decide to vote by mail, and 10 percent of their votes are lost due to mistakes, then we’ve lost 100 votes we otherwise should have had.”

The worries about honest mistakes are part of the reasoning behind the shift in Philadelphia. Officials there recently warned that a decision from the State Supreme Court instructing officials to discard so-called “naked ballots” — those that arrive without a secrecy envelope — could risk up to 40,000 votes in the city. That’s a significant amount in a Democratic city where Mr. Biden needs to run up the margins to have a chance at winning back Pennsylvania.