Mr. Trump’s supporters, by contrast, often project serene confidence about how their candidate will perform against Mr. Biden.
Mr. Trump “is going to eat him up and spit him out,” said Maria Tiernan, 80, a retiree who saw the former president speak at a rally on Saturday in Philadelphia. “I’m going to make popcorn. I’m having a party.”
“Trump has him in the debate, hands down,” said Emmett Taylor, 67, of Camden, N.J.
Several of Mr. Trump’s supporters worried that he wouldn’t be treated fairly by the debate’s moderators, Jake Tapper and Dana Bash of CNN. But the sky-high expectations his supporters have for his personal performance, as well as their low expectations for Mr. Biden, could become a problem for Mr. Trump — one he seemed to try to get ahead of at the Saturday rally by crudely suggesting that a strong performance by Mr. Biden could come only if he was using drugs.
“This is a great opportunity for Biden,” said Mark Longabaugh, a Democratic strategist who worked on Senator Bernie Sanders’s 2016 presidential campaign. “If he goes in there and exceeds the expectations of the chattering class, I think he comes out with a win.”
Frances Malone, 68, an independent voter in Columbus, Ga., who is disappointed that Democrats didn’t seek a successor to Biden for this year’s election , said she was deeply troubled by the possibility of Mr. Trump’s winning the election — particularly after the attack on the Capitol by his supporters on Jan. 6, 2021. The debate, she said, is “just something that has to be done.”
She is reserving some hope, however, that Mr. Biden will surprise her.
“I have a childish wish to see Donald Trump lose his mind on camera — if he can somehow get Trump to show his true colors, it wouldn’t be the worst thing for me,” she said. “I hope we see the strongest Joe Biden out there.”
Simon Levien contributed reporting.