These voters supported Biden in 2020. But now…

Jeanne Winograd, 72, a Phoenix Democrat, is such a ride-or-die fan of President Biden that she sent him a card on Valentine’s Day saying that his strength, not his age, would decide the election. But after a week of panic attacks following his poor debate performance, she felt compelled to send him another card.

This one said: Thank you for everything, but it’s time to go.

“I just love Biden, but he’s weak,” Ms. Winograd said. “Pass the baton.”

As Mr. Biden and his allies rush to repair the damage from last week’s debate and insist that he not withdraw from the race, dozens of Democratic voters have said they no longer believe he can achieve the one thing they desperately want: a defeat of former President Donald J. Trump. They are desperate for the party to find a Plan B.

In 80 interviews at Independence Day parades, pie-eating contests and political events this holiday in the political battlegrounds of Arizona, Michigan, Wisconsin and North Carolina, more than half of voters who cast their ballots for Biden in 2020 said he should drop out of the race. About a quarter said he should stay in. The rest were undecided.

The turmoil that had gripped the Democratic Party had left them sleepy and divided over the path forward. Some said it would be pragmatic to dump Biden, while others argued that he was the Democrats’ best — or only? — option in November.

Several voters said Vice President Kamala Harris was the smartest replacement for Mr. Biden. But others Worried she couldn’t match Mr. Trump, she suggested the Democratic governors of Michigan or Pennsylvania might be a smarter choice. How about one of the Castro brothers from Texas, one voter suggested. Another asked: How about Michelle Obama?

All but one voter said they would still vote for Mr. Biden if he remained in the race. They said they saw Mr. Trump as a greater threat to democracy, women’s rights and the future of the world than Mr. Biden, who would be 86 at the end of his second term. They also said they believed Mr. Trump, 78, was not mentally equipped to serve another four years.

Some also worried about the risks of abruptly replacing a presidential candidate four months before an election, and about the growing sense that the party did not know what to do.

“We can’t agree on the way forward, we can’t agree on what to do about the current situation,” said Raja Seshadri, 46, who works at the National Institutes of Health in Raleigh, N.C. “We’re going to lose.”

The willingness of Democratic voters to publicly consider firing Biden stands in stark contrast to what they hear from their own leaders.

While two Democratic incumbents in Congress have called for Biden to be ousted, a large majority of Democratic elected officials backed him this week, even as a new poll from The New York Times and Siena College showed Trump with a six-point lead over Biden among likely voters.

Some voters said they felt frustrated and betrayed by their party’s efforts to suppress any discussion of whether Mr. Biden should step aside. They said Mr. Biden’s meandering answers during the debate couldn’t be explained away as a bad night, or the product of jet lag or a cold, and they weren’t reassured by his performances at afterward events.

“It’s outrageous that they let him come here and we’re all here,” said Elaine Becherer, a 48-year-old who works in university planning in Phoenix, as she and other Biden voters in Arizona discussed his candidacy on a video call this week.

“Our ‘beloved leader,’” Cristina Ospina, a 56-year-old Phoenix neurologist who studies movement disorders, said sarcastically, referring to North Korea’s flattering description of its leader, Kim Jong Un.

Some frustrated Democratic voters are openly expressing their concerns.

Some said they were writing letters to the White House and reaching out to local elected officials. In Traverse City, Mich., Greg Holmes, 71, a retired psychologist and loyal Democratic voter, showed up at a campaign appearance for the first lady, Jill Biden, carrying a sign that read, “Step Aside Joe!”

“If Biden says and does what I call the right thing or the courageous thing and passes the baton, I will be overjoyed and excited for the next person,” Holmes said. “Because I think Trump really is a terrible, terrible threat to our democracy.”

Mr. Holmes said he did not believe Mr. Biden was fit to serve as president, and that he did not believe the Democratic Party and the Biden campaign had been honest with voters. At this point, he said, the best course of action would be for Mr. Biden to release his delegates to the Democratic National Convention and let them decide on a new nominee.

In the predominantly Democratic Milwaukee suburb of Wauwatosa, the Biden campaign’s troubles were not far from the forefront of many voters’ minds as they watched high school bagpipers and dance teams march in the city’s annual Independence Day parade.

“He should be out of the race,” said Gerry Ford, a 72-year-old engineer (and not the 38th president of the United States). “The sooner the better. He doesn’t meet the criteria for the most important job in the world.”

Ford also said the White House and Biden’s campaign had not been transparent after the debate.

“It confirms all our suspicions about politicians that they can’t be honest with voters,” he said. “It’s embarrassing for the country.”

Down the street, Sophia Artus and Emma Due, both 18, said they were unenthusiastic about either presidential candidate in the first ballots of their lives. They were so discouraged by the debate that they turned it off midway through. They said they would probably vote for Mr. Biden, but only because he was not Mr. Trump.

“Kamala Harris would carry the torch, and she’s better than Trump,” Ms. Due said. “There are a lot of new ideas that younger people are expressing, but you don’t see that reflected in our candidates.”

Other Democrats have decided to ignore their concerns and stick with Biden.

Melissa Wicksel, 21, of Raleigh, N.C., said defeating Mr. Trump was so important that Democrats had to rally behind Mr. Biden and highlight his policy accomplishments. She said her Democratic friends had also voiced their support for Mr. Biden.

“He stutters, he’s older, that’s for sure, but generally, if you listen to what he says, I understand him,” Ms. Wicksel said. “Trump, on the other hand, lies all the time.”

Liz Purvis, chair of the Democratic Party of Granville County in North Carolina, a purple county that Trump won in 2020, said her take on the internal party debate right now is simple: “Frankly, I think sticking with Biden is the right thing to do.”

“With the money they raised and the organizing power that the coordinated campaign has, our smoothest path to a Democratic victory feels to me like it is through a Biden campaign,” Ms. Purvis said.

She added that “it feels like the infighting doesn’t mean progress, and what we need is progress.”

In Tempe, Ariz., Michael John, 35, said he decided to cast his first ballot in November after starting his own small business, Navajo Mike’s, which makes fry-bread mix and barbecue sauce. He realized how deeply politics was intertwined with his life, family and success. Mr. John, a Navajo citizen, said Mr. Biden supportive Native-owned businesses like his with loan guarantees and help with marketing and business development. But he also said he believed Biden should withdraw from the race to avoid losing to Trump.

“It would be ideal to have someone who is more coherent and engaged and there,” he said, adding that President Biden “should go do something cool and fun. You don’t need the burden of the world on your shoulders.”