HOOKSETT, N.H. – Voters in New Hampshire, a key northeastern swing state, say President Biden's extremely rough performance two weeks ago in his debate with former President Trump will weigh heavily on their decision of whom to support in the 2024 election rematch.

"I'm leaning toward Donald Trump a little bit. Just because, I mean, the debate performance is really, really, really impactful for me, I was really thrown off by Joe Biden's performance," a New Hampshire voter named Mario, told Fox News.

Mario and nearly a dozen other voters shared their views as they stopped Monday at a highway rest area about half between the state capital of Concord and Manchester, which is New Hampshire's largest city.

Following his extremely rough debate performance in his first face-to-face showdown with Trump, Biden has been attempting to prove that he still has the stamina and acuity to handle the toughest and most demanding job in the world. And he's trying to prove that he has the fortitude to defeat Trump.

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The debate was a major setback for Biden, who at 81 is the oldest president in the nation's history. His halting delivery and stumbling answers at the showdown in Atlanta sparked widespread panic in the Democratic Party and a rising tide of public and private calls from within his own party for him to step aside as its 2024 standard-bearer.

Over the past week and a half, six House Democrats have publicly called on Biden to end his re-election bid. And on Sunday, Fox News and other news organizations reported that four House Democrats who hold top positions on key committees said on a private conference call that the president needed to step aside.

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Biden, in a letter sent to congressional Democrats on Monday as they returned from the July 4th holiday recess, reiterated that he's "firmly committed to staying in this race" and argued that "the question of how to move forward has been well-aired for over a week now. And it is time for it to end. We have one job. And that is to beat Donald Trump."

"Any weakening of resolve or lack of clarity about the task ahead only helps Trump and hurts us," the president added. "It is time to come together, move forward as a unified party, and defeat Donald Trump."

Mario shared, "I'm not really a Donald Trump person," adding, "I think Donald Trump is too old, too."

"But, I mean, out of the two, to me, he was a little bit younger, a little bit more with it. So that's where I'm leaning toward at the moment."

William Yacopucci, another New Hampshire voter, said Biden has "been an awesome president. I really like him. I think he can still do a good job for the remainder of this term."

But, he added, "Three or four years from now, he's going to be that much older. So, though I really, really like him, I think they should give someone else another shot at it."

New Hampshire voter Al Byrnes told Fox News he "was very sad that President Biden performed like he did, but in the concept of everything, I would still totally back him tomorrow at this point."

"I do wish that he would drop out of the race, but, I would support him or whoever replaces him. Anything but Donald Trump," Byrnes emphasized.

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Rose, another New Hampshire voter who said she was leaning toward Trump, offered, "Biden doesn't seem like he knows what he's talking about."

But taking aim at the debate performances of both Biden and Trump, she added, "I felt like they were both just talking circles around each other."

The voters were interviewed minutes before Gov. Gavin Newsom of California, who's a top surrogate for Biden's re-election campaign, arrived at the highway rest area and took aim at the small but growing number of Democratic lawmakers urging the president to end his re-election bid. 

"It doesn’t help. Let’s be candid here," Newsom said as he spoke with reporters in New Hampshire, the third swing state that the governor has campaigned in on behalf of Biden since Thursday.

Asked by Fox News about the political damage from such calls from within the party, Newsom said, "Obviously, it’s not helpful, but it’s a handful of people."

And the governor emphasized that the "overwhelming majority of the caucus" is still supporting Biden. "Every single stop that we’ve had in the six days that I’ve been out, we’ve had to change venues because there were so many people showing up. They’re not giving in to the cynicism, fear, they’re showing up."

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Newsom spoke with reporters soon after White House officials defended Biden's health and denied he was ever treated for Parkinson’s disease. White House press secretary Karine Jean-Pierre fielded a barrage of questions on Monday afternoon over recent reports that a top neurologist at Walter Reed National Military Medical Center met with Biden’s physician at the White House in January.

"Has the president been treated for Parkinson’s? No," she told reporters after being pressed further on the matter. "Is he being treated for Parkinson's? No, he’s not. Is he taking medication for Parkinson’s? No. So, those are the things that I can give you full-blown answers on."

Asked if he had any concerns about Biden's cognitive abilities, Newsom responded, "I don’t."

"I have spent as much or more time than probably any other governor in the country with him," Newsom emphasized. "I’ve spent a lot of time with him privately, been with him in many public settings. I was with him just a few days ago with other governors. Been on the phone late at night and early morning, in many, many stressful situations and very casual conversations. And no, I don’t have any doubt about that."

A handful of national polls conducted entirely after the debate and released last week contained plenty of red flags for the president – including Trump widening his single-digit edge over Biden and deepening concerns of Americans about whether Biden was up to the task of running the country.

Despite his denials, Newsom's name continuously comes up in media reports as a potential replacement should the president change his mind and decide to end his re-election campaign.

"I think that’s a legitimate question and I respect it," Newsom said when asked if he would seek the nomination at next month's convention in Chicago if the president bows out.

But, he quickly added, "It’s also exactly the question that Donald Trump is hoping everyone asks as he’s out on the golf course."

Asked if the media attention was an intentional distraction, the governor said, "Of course it is."

"Look. It’s intentional. I know how these guys work," Newsom charged, as he pointed toward conservative media. "This is all very intentionally ginned up in order to create a little mishegoss (a Yiddish word for crazy or senseless behavior or activity)." 

Newsom said, "I don’t take it personally. I don’t take it seriously except to say sometimes I do believe others do take it more seriously than they should."

And, he argued, "I think it’s intentional mis- and disinformation and it can be very effective, and we have to counter that and that’s why I’m out here."

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