Donald Trump works the fry station at a Pennsylvania McDonald's

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FEASTERVILLE-TREVOSE, Pa. — Republican presidential nominee Donald Trump manned the fry station at a McDonald's in Pennsylvania on Sunday before staging an impromptu news conference, answering questions through the drive-thru window.

As reporters and aides watched, an employee showed Trump how to dunk baskets of fries in oil, salt the fries and put them into boxes using a scoop. Trump, a well-known fan of fast food and a notorious germophobe, expressed amazement that he didn't have to touch the fries with his hands,

“It requires great expertise, actually, to do it right and to do it fast,” Trump said with a grin, putting away his suit jacket and wearing an apron over his shirt and tie.

The visit came as he's tried to counter Democratic nominee Kamala Harris' accounts on the campaign of working at the fast-food chain while in college, an experience that Trump has claimed — without offering evidence — never happened.

A large crowd lined the street outside the restaurant in Feasterville-Trevose, which is part of Bucks County, a key swing voter area north of Philadelphia. Later Sunday, Trump was attending an evening town hall in Lancaster before catching the Pittsburgh Steelers home game against the New York Jets.

After serving bags of takeout to people in the drive-thru lane, Trump leaned out of the window, still wearing the apron, to take questions from the media staged outside. The former president, who has constantly promoted falsehoods about his 2020 election loss, said he would respect the results of next month's vote “if it's a fair election.”

He joked about getting one reporter ice cream and when another asked what message he had for Harris on her 60th birthday on Sunday, Trump said, “I would say, Happy Birthday, Kamala,” adding, “I think I’ll get her some flowers.”

Trump did not directly answer a question of whether he might support increased minimum wages after seeing McDonald’s employees in action but said, “These people work hard. They’re great.”

He added that “I just saw something… a process that’s beautiful.”

When aides finally urged him to wrap things up so he could hit the road to his next event, Trump offered, ‘Wasn’t that a strange place to do a news conference?’

Trump has long questioned Harris' story of working at McDonald's

Trump has fixated in recent weeks on the summer job Harris said she held in college, working the cash register and making fries at McDonald’s while in college. Trump says the vice president has “lied about working” there, but not offered evidence for claiming that.

“When Trump feels desperate, all he knows how to do is lie,” Harris campaign spokesman Ian Sams said Sunday. “He can’t understand what it’s like to have a summer job because he was handed millions on a silver platter, only to blow it.”

In an interview last month on MSNBC, the vice president pushed back on Trump’s claims, saying she did work at the fast-food chain four decades ago when she was in college.

“Part of the reason I even talk about having worked at McDonald’s is because there are people who work at McDonald’s in our country who are trying to raise a family,” she said. “I worked there as a student.”

Harris also said: “I think part of the difference between me and my opponent includes our perspective on the needs of the American people and what our responsibility, then, is to meet those needs.”

Trump has long spread groundless claims about his opponents based on their personal history, particularly women and racial minorities.

Before he ran for president, Trump was a leading voice of the “birther” conspiracy that baselessly claimed President Barack Obama was from Africa, was not an American citizen and therefore was ineligible to be president. Trump used it to raise his own political profile, demanding to see Obama’s birth certificate and five years after Obama did so, Trump finally admitted that Obama was born in the United States.

During his first run for president, Trump repeated a tabloid’s claims that Texas Sen. Ted Cruz’s father, who was born in Cuba, had links to President John F. Kennedy’s assassin, Lee Harvey Oswald. Cruz and Trump competed for the party’s 2016 nomination.

In January of this year, when Trump was facing Nikki Haley, his former U.N. ambassador, in the Republican primary, he shared on his social media network a post with false claims that Haley’s parents were not citizens when she was born, therefore making her ineligible to be president.

Haley is the South Carolina-born daughter of Indian immigrants, making her automatically a native-born citizen and meeting the constitutional requirement to run for president.

And Trump has continued to promote baseless claims during this campaign. Trump said during his presidential debate with Harris that immigrants who had settled in Springfield, Ohio, were eating residents’ pets — a claim he suggested in an interview Saturday was still true even though he could provide no confirmation.

Trump's visit created a spectacle in Pennsylvania

Police closed the busy streets around the McDonald’s during Trump's visit. Authorities cordoned off the restaurant as a crowd a couple blocks long gathered, sometimes 10- to 15-deep, across the street straining to catch a glimpse of Trump. Horns honked and music blared as Trump supporters waved flags, held signs and took pictures.

John Waters, of nearby Fairless Hills, had never been to a Trump rally and had hoped to see the former president so close to his house after missing other nearby rallies.

“When I drove up, all the cars, unbelievable, I was like, ‘He’s here’s, he’s coming, he’s definitely coming with this all traffic,’” Waters said.

Trump is especially partial to McDonald's Big Macs and Filet-o-Fish sandwiches. He’s talked often about how he trusts big chains more than smaller restaurants since they have big reputations to maintain, and the former president’s staff often pick up McDonald’s and serve it on his plane.

Barrett Marson, a Republican strategist in Arizona, said using a campaign visit to focus on the claims about McDonald's four decades ago is a “puzzling detour,” but that Trump is “not above throwing anything on the wall to see if it sticks.”

“When Donald Trump isn’t talking about the economy and illegal immigration, he’s off topic about the things that people care about,” Marson said.

Associated Press writer Will Weissert in Washington contributed to this report.