ROCHESTER, N.H. — For a politician who once railed against the dynastic politics of the Clintons, Sen. Bernie Sanders has a significant, albeit less successful, family business of his own.

Last year, his brother, Larry, 82, ran for the British Parliament and lost as a Green Party candidate. Earlier this year, his stepdaughter, Carina Driscoll, 45, ran for his old job of mayor of Burlington, Vt., but lost. She, like Sanders, ran as an independent.

Now his son, Levi, 49, is running in Tuesday’s primary to replace retiring Rep. Carol Shea-Porter (D) in New Hampshire’s 1st District, a swing seat the elder Sanders won by 22 points in the 2016 Democratic presidential primary. Levi is his only biological child, from his ex-girlfriend Susan Mott Glaeser, and has been a mainstay of Bernie Sanders’s political career since appearing with him on the campaign trail at age 2.

The younger Sanders has not only the ruddy complexion, ruffled hair and cantankerous style of his father, whom he affectionately refers to as “Bernard,” but also a cookie-cutter Sanders agenda based on Medicare-for-all and a $15-an-hour minimum wage.

What he doesn’t have is his father’s endorsement.

“In the Sanders family, we don’t ‘do’ dynastic politics,” he explained.

Does he have any political differences with his father? “No,” said Sanders, whose campaign website is decorated with pictures of the pair together and calls for a system that “represents the 99 percent, not the 1 percent who have never had it so good,” a line lifted straight out of Bernie’s primary playbook from 2016.

During that campaign, Sanders worked for his father as a senior strategist and appeared with him at rallies as the Vermont senator sought to soften his image. “Bernard’s campaign was similar to mine in that he didn’t get any of the media or the establishment to support him. But people were saying to me, ‘Your father has changed me, I feel alive and awakened.’ It was amazing,” he recalled.

Bernie Sanders has not discussed his son’s race beyond a statement he issued in June. At a Labor Day event in Manchester, he briefly introduced Levi Sanders but did not campaign with him.

“Levi has spent his life in public service to low-income and working families, and I am very proud of all that he has done. In our family, however, we do not believe in dynastic politics. Levi is running his own campaign in his own way,” the senator said in his earlier statement.

The refusal by Bernie Sanders to endorse his son is all the more stark given Levi’s dire circumstances in his improbable run for the House.

The married father of three spent his career working at a food bank and then in legal services, helping people apply for health and disability aid, but beyond an abortive bid for Claremont City Council 10 years ago, he has no personal political experience.

“I was talking to a woman about the cost of prescription drugs, and she told me she had to cut her pills in half. She told me I should run. I thought about it, and I did,” he said. He then took a swipe at his rivals with trademark familial ire. “With stories like that, I don’t know what goes through their head when they don’t believe in single-payer health care!”

Sanders has raised just $39,000, which, he says, means a basic list of voters’ names and addresses exceeds his budget. Analysts believe he is well behind what he calls the “establishment” front-runners: former Obama administration official Maura Sullivan, with $1.8 million raised, and Manchester councilor Chris Pappas, at $800,000.

He was deemed so marginal, complained his campaign manager Marie Clark, who cut her teeth as a Vermont canvasser on Bernie Sanders’s 2016 campaign, that he was not invited to a recent debate.

He has lived in New Hampshire for 15 years with his wife and children, but their Claremont home lies outside the district and he has been accused of being a carpetbagger. He dismisses such criticism as a “swamp” issue.

“What people are interested in is whether I back universal health care, not things that divide people into ‘us’ and ‘them,’ ” he said. His name recognition is low, and at a county fair in Rochester, a group of teens asked if he was Sanders’s brother. “I get that a lot!” he said.

Bernie Sanders’s backing has proved important for some Democratic Socialists throughout the country, yielding national attention and crucial campaign donations. Yet Sanders, who embraces the Democratic Socialist platform, insists he does not rue the lack of support. In part, this is because his link to the senator is obvious, but also because he rejects nepotism.

“It’s interesting psychologically, but you just build a lot more confidence and self-worth when you do things on your own. When things are given to you, you don’t get a sense of self and the adversity,” he said. “The fact is that my father supports me, you’ll see some of the things he’s said about me, but he believes I need to do this on my own, and I feel fine.”

Sanders added that dynasties are unpopular. “It’s not something that people are into, they’re not into nepotism. I feel it’s important for me to do it on my own. If you and I pulled over, people would say, ‘You need to do it on your own.’ ”

That thesis has mixed results. Shayla Almeida, 24, a machine operator at aerospace manufacturer Pratt & Whitney, raced up to Sanders to ask for a selfie. “Some people use the name for their income or use it for their campaign. I like that he doesn’t,” she said. “I really like what he says.”

“I like it too,” says her mother, Susana, a cake baker.

Still, neither intend to vote for Sanders, saying they will side with a better-financed candidate who will stand up for gun-control laws and single-payer health care.

Dirk O’Brien, 57, a father of three and an ex-Marine who spent time in a shelter for veterans, disagreed.

“He should support his son,” he said of the elder Sanders. “There’s no blueprint for being a parent, I get it, but your responsibility is to make sure your kids get what they need. I’m not saying he didn’t, but you know what I mean? That’s just the way I feel, and I like Bernie.”

Levi Sanders said his political ambitions will not be over even if he loses. “Initially, my father didn’t do well,” he says, citing the gubernatorial and senate campaigns where he won just 6 percent of the vote before becoming mayor of Burlington. “I’ve got a lot of that never-say-die attitude and not giving up. ... Running has been interesting and gratifying and I’ve learned a lot about people and their emotions and what I can do to advocate for their interests.”

And he insists his relationship with his father will not be affected whatever the outcome. “Growing up, my father and I, we’d play basketball and chess and watch ‘Star Trek,’ ” he recalled. “But when I was little, when kids were in the sand pit, I was thinking about politics. We have always had a close relationship. . . . That won’t change.”

And does he back a Sanders 2020 bid?

“Do I think Bernard Sanders would make be good president? Absolutely. I think he’d be an excellent candidate,” he said, before adding a caveat. “Now all the favorites back Medicare-for-all. That wasn’t mainstream. Today, it’s mainstream,” he said. “So I will campaign for whoever wins that primary.”