As JD Vance takes heat, Trump fans rally to his side

But the Nevadans who turned out to hear Vance Tuesday saw him as something else: Trump’s handpicked heir.

“I came to see what the future of the GOP looks like," said Kate Marsh, 38 years old, a local property manager. “Vance is who Trump picked to carry us on after he’s gone."

Vance, a 39-year-old Ohio senator first known for his “Hillbilly Elegy" memoir, has been seeking to define himself on the campaign trail since Trump chose him at the start of the Republican convention. The decision, which came before President Biden announced he would step out of the race, has been second-guessed by some Republicans since, as Vance is seen as a populist, right-wing messenger who appeals to Trump’s loyal MAGA base but may not to the voters needed to win a close race in swing states such as Nevada.

Vance dedicated most of a fiery speech before a cheering crowd in Reno Tuesday to bashing Vice President Kamala Harris, the Democrats’ expected nominee, calling her “dangerously liberal." He slammed Harris for policies he claimed had led to an influx of immigrants entering the country illegally, vowing mass deportations if Trump is elected. He bashed free trade, globalization and the media. He sought to equate Harris with Biden, suggesting she acted for him behind the scenes.

“If you’re too dumb to realize that Biden couldn’t do the job or, more likely, if you’re too dishonest to admit it, you are not fit to be commander in chief," Vance said.

Like Trump, Vance favors tighter borders, tariffs, more isolationist foreign policy and government intervention in the economy. He has echoed Trump’s antiestablishment message and, in his acceptance address, bashed Wall Street.

In the weeks since the pick, Vance has drawn unwanted attention for several past comments, most notoriously for calling the country run by “a bunch of childless cat ladies who are miserable at their own lives" in a 2021 interview and calling for people without children to pay higher taxes.

In the face of the perceived flubs, Republicans have faced questions as to whether Vance is the right person for the ticket.

“Well, it’s too late to rethink it," said Sen. Kevin Cramer (R., N.D.), who had advocated for North Dakota Gov. Doug Burgum to be the vice presidential pick. Cramer added that he isn’t worried about the comments Democrats have pounced on since the nomination.

Sen. Eric Schmitt (R., Mo.) said Vance was a great pick and dismissed private griping among Republicans.

“That’s a lot of drama in the bubble here," Schmitt said, referring to inside-the-Beltway speculation about whether Vance would be replaced on the ticket. “I don’t think that’s real."

Trump has taken note of some of Vance’s comments and the criticism that has accompanied them, according to people familiar with his thinking, and he is closely watching Harris in these early days to evaluate where things stand for his campaign.

But the Trump campaign pushed back on any suggestions that the GOP nominee is having second thoughts.

“President Trump is thrilled with the choice he made with Sen. Vance to be his running mate, and they are the perfect team to take back the White House," said campaign spokesman Steven Cheung. “Democrats are in complete disarray after their coup that forcibly removed Biden from the campaign, proving they are the real threats to democracy. The fact remains that Kamala Harris is weak, failed, and dangerously liberal, and no amount of gaslighting from her or her campaign will erase her despicable record," he said.

Harris campaign spokeswoman Sarafina Chitika said Tuesday that Vance’s past comments “make it clear: he and Donald Trump are not pro-family, they are anti-women."

At Tuesday’s rally, Florida Rep. Anna Paulina Luna defended Vance against that charge. “I am here today because of the egregious lies about JD Vance, that he’s anti-woman," Luna said. “They try to say that JD is the problem, but the fact is he’s a threat" to Democrats.

In a brief personal part of his speech, Vance mentioned his wife and the grandmother who raised him. “I have been the beneficiary of a number of strong women in my life," he said. “I’ve lived the American dream because of those strong women."

Marsh, the property manager, said she knew nothing of Vance before Trump added him to the ticket but, in the two weeks since, has read his book and differing opinion pieces about him. She called herself fascinated by his “American dream" story and wants to hear more of his perspectives on policy.

Marsh and other rally attendees largely shrugged off the recent knocks Vance has taken. Turning out in bedazzled MAGA hats and T-shirts with photos of a bleeding Trump after the attempt on his life, they said they had confidence in any Trump choice.

Shawn Newman, a 59-year-old truck driver, tried to camp in the parking lot—as he has at other Trump rallies—to be first in line to see Vance, he said. When security kicked him out at 2 a.m. he moved across the street, he said, then returned at 5 a.m.

“Whoever Trump picks, I’m going to stand behind, because everything Trump has said has come true," Newman said.

Retirees John and Jessie Vettel, who were previously familiar with Vance and were asked to sit behind him onstage, said they were most impressed by his personal background and accomplishments.

“He knows what it’s like to struggle," John Vettel said.

“And right now a lot of us are struggling," his wife added.

Rally attendee Todd Stubblefield, 63, a contractor working temporarily in Reno from Houston, Tex., said he didn’t know anything about Vance before the speech but, afterward, was a fan.

“I like his passion," Stubblefield said. “I like the fact that the Democrats are throwing bricks at him."

More moderate voters in the swing state, however, said they were alarmed by Vance.

Steve Weil, 62, a Carson City independent who described himself as fiscally conservative and socially progressive, called the vice presidential nominee even more extreme than Trump.

“His abortion stance is definitely more extreme," said Weil, a retired surgical nurse. “His comments regarding needing to have children in order to have a vested interest in the future of our country, I find that disingenuous."

Lindsay Wise, Vivian Salama and Alex Leary contributed to this article.

Write to Elizabeth Findell at elizabeth.findell@wsj.com