By the time former President Donald J. Trump was convicted last week on 34 felony counts, the vast majority of people had made up their minds about him.

But a small sliver of Trump-ambivalent voters is out there — and in a close presidential election, they matter a lot.

For days, The New York Times has been listening to those voters process the news of Mr. Trump’s conviction, trying to measure the small shifts that could alter the contest between him and President Biden. Will Trump-leaning voters move firmly into his camp? Will Biden-leaning voters get off the fence?

A New York Times/Siena College Poll study of nearly 2,000 voters found modest good news for Mr. Biden. While the vast majority of people had not changed their position on the two men, more voters moved away from Mr. Trump than toward him.

Follow-up interviews with these post-verdict switchers offer a window into the minds of still-persuadable Americans. Despite the big events and dramatic headlines, these voters said they were generally not fans of either candidate, they were in no hurry to decide and they might not vote at all.

Here’s a look at how this small, but potentially crucial, group of voters is thinking about Mr. Trump’s conviction and how it might affect their choice for president in November:

Jack Lyons, Reno, Nev.

Mr. Lyons, 65, owns catering and welding companies and a boat storage facility. Earlier this year, he said he considered himself a Trump voter primarily because of his anger over Mr. Biden’s economic policies — even though he said he opposed Republican attempts to limit abortion rights.

But when he heard about Mr. Trump’s conviction on the local Fox News radio affiliate in northern Nevada, Mr. Lyons began to rethink his vote this fall. He said he had taken “a step back” to wait and see if the former president serves jail time.

“I want to see what happens with Donald Trump going forward. What’s going to happen with him? Is this judge going to put him in jail?” Mr. Lyons said in an interview on Tuesday. “I’m not sure who I am going to vote for — or if I am going to vote.”

Despite being in favor of abortion rights, Mr. Lyons said he was disinclined to vote for Mr. Biden because he did not believe the president is on the side of small business owners. If he disqualifies Mr. Trump in his mind, he said he could back an independent candidate like Robert F. Kennedy Jr.

“If I could vote and I knew that Kennedy would have a real shot, I would vote for him,” Mr. Lyons said.

Eric Tabor, Albany, Ga.

There was a brief period recently when Mr. Tabor, 53, a tech professional, figured he would vote for Mr. Trump this year.

“What got me was that he seemed to be able to get things accomplished and pushed through,” said Mr. Tabor, who is a Democrat and voted for Hillary Clinton in 2016 and Mr. Biden in 2020. “You need a person in that chair that’s going to be decisive and can get Congress and the legislature behind you.”

Mr. Tabor said he had turned to Mr. Trump after Mr. Biden’s student loan forgiveness plan was rejected by the Supreme Court, and Mr. Tabor was left with the feeling that the president was getting little done. He also worried Mr. Biden, 81, is too old to be president, Mr. Tabor said, and began looking more favorably at Mr. Trump, who is 77.

But after Mr. Trump’s conviction last week, Mr. Tabor said he was no longer so sure about the Republican. The Manhattan trial, on charges of falsifying business records related to hush-money payments paid to a porn star, made Mr. Tabor question Mr. Trump’s honesty.

“My thing is just go ahead and be honest. We, as Americans, we can respect that. A lot of people make mistakes,” Mr. Tabor said, adding that he worried that Mr. Trump would seek retribution against Democrats. “We all know if Donald Trump gets re-elected, he’s going to try to be a dictator and he’s got his ‘I’m going to get you’ list.”

Now, Mr. Tabor is researching third-party candidates and said there was little Mr. Biden or Mr. Trump could do to change his vote besides nominating a reliable vice president. “I don’t know if either one of them — because of their age and the demands on the president — would make it four more years.”

Jamie Beckwith, Butler, Pa.

Ms. Beckwith, a 41-year-old accountant, voted for Mr. Biden in 2020 but has been undecided about whether she will do so again. She blamed him for not saving abortion rights after the Supreme Court overturned Roe v. Wade in 2022. And she said Mr. Biden shares blame for the deaths of civilians in Gaza because his government has supplied weapons to the Israeli military.

“The fact is that it is our bombs on the ground that these people are dying from,” she said. “There’s nothing happening from Biden other than encouraging it, in my opinion, or, you know, by continuing to fund it and not saying, ‘Enough is enough.’”

Ms. Beckwith volunteers with people trying to rebuild their lives from addiction and prison sentences, she said. She found the prospect of a felon running for president, moving on as if nothing had changed, frustratingly unfair.

“If a person who received 34 felony convictions in one day still ran for president, why can my guy not apply for a job at a gas station?” she said. “I look at it from the standpoint not of, you know, ‘Oh, Trump’s guilty.’ I don’t care. It’s the fact that he can still carry on his life without any kind of hurdles.”

She said she was now likely to vote for Mr. Biden in November.

Carla Watts, Fairburn, Ga.

Ms. Watts, a 52-year-old account executive for a telecommunications company, is a Democrat who voted for Mrs. Clinton and Mr. Biden the last two elections. But she watched Mr. Biden perform the job as president and could not envision voting for him again.

“Sometimes Biden says things without thinking,” she said.

Like many Democrats unenthused about the president, Ms. Watts said her choice came down to voting for Mr. Biden or sitting out this year’s election. She said she was never going to vote for Mr. Trump — his guilty verdict did not change her view of the former president — but she has eventually come around to the idea of voting again for Mr. Biden.

“My dad was in the civil rights movement, and they fought hard for us to even have the right to vote,” Ms. Watts said. “So to not vote is like a smack in my father’s face.”