David Trone, a Democrat seeking Maryland’s 6th Congressional District seat, poses with Harbin Singh, 14, outside the polling station at Robert Frost Middle School in Rockville, Md., on June 26, 2018. Harbin, who was serving as an electioneer for a different candidate, said he wanted the photo because he thought Trone was really famous. He said that his parents had a photo with Bill Clinton and that he had to compete with them. (Bonnie Jo Mount/The Washington Post)

David Trone, the Potomac tycoon, won the Democratic primary for the House seat being vacated by Rep. John Delaney in Maryland, overcoming rivals’ criticism that he sought to buy the race by pumping more than $10 million of his own money into the campaign.

Trone, the owner of Total Wine & More, a national liquor store chain, will face Republican Amie Hoeber in November for Maryland’s 6th Congressional District seat. Hoeber, a defense contractor, easily won the GOP primary.

Trone, 62, was victorious in a Democratic field of eight candidates that included state Del. Aruna Miller (D-Montgomery), who had the backing of Emily’s List and more than two dozen Maryland state lawmakers.

At a time when Maryland’s congressional delegation is all-male and record numbers of women are running for office, Miller hoped her gender would help propel her candidacy. But Trone’s massive financial advantage — he outspent Miller 11 to 1 — overwhelmed his opponents.

Trone’s victory came two years after he lost his first race for Congress, a campaign in which he spent $13 million of his own money but lost to Rep. Jamie Raskin (D) in Maryland’s 8th District.

“Let’s celebrate tonight,” Trone told supporters at a victory party in which he was introduced by Delaney, himself a multi-millionaire who won the seat after a career in business. “Now we must win in November against a Republican opponent who has demonstrated no empathy whatsoever, no compassion for the families that are separated on the border.”

State Del. Aruna Miller (D-Montgomery), a candidate for Maryland’s 6th Congressional District seat, speaks with voters outside the polling station at Gaithersburg Church of the Nazarene in Gaithersburg, Md., on June 26, 2018. (Bonnie Jo Mount/The Washington Post)

“Congress has demonstrated a lack of civility, a lack of confidence, no compassion that borders on cruelty,” he said.

With Delaney’s decision to leave Congress to run for president, the 6th District campaign was the most competitive of Maryland’s congressional races Tuesday, in which eight incumbents won their primaries.

Sen. Benjamin L. Cardin (D) easily beat back challengers who included Chelsea Manning, the former intelligence analyst who served time in prison for leaking classified intelligence information, and Jerome “Jerry” Segal, a philosopher and progressive activist who spent $1.4 million on his race.

On the Eastern Shore, four-term incumbent Rep. Andy Harris won the Republican primary in the 1st Congressional District. Jesse Colvin, 33, an Army veteran, won the Democratic primary.

In the 6th District, the candidates espoused similar positions and relied on their personal stories to bond with voters spread across a gerrymandered district that includes five counties.

What distinguished Trone was his willingness to pour his own money into the race, allowing him to hire multiple consultants and inundate the district’s airwaves with advertising touting his rise from a family farm in Pennsylvania to become the co-founder of a national business chain.

But Trone’s spending also exposed him to criticism that he was seeking to buy a congressional seat, a charge buttressed by his failed campaign two years ago.

As he voted in Frederick, Zack Willis, 24, who works for a local nonprofit, said Trone’s ubiquitous presence on social media and television overshadowed the candidate’s pledge that he would be a champion of the little guy.

“If you see David Trone, tell him to cool it with the mailers,” Willis said. “He’s all over my Facebook, my Instagram, my Twitter.” Rather than demonstrating a desire to win, Willis said, Trone’s campaign advertising “emphasizes” the candidate’s “privilege.”

But Glen Velez, 63, who works in hotel security, said he voted for Trone to be a check on the conservatism of President Trump. “It’s like night and day from Obama to Trump,” Velez said after voting in North Potomac. “It’s frightening actually.”

Miller’s advantages included her gender and background as an immigrant in a year when female candidates are helping to shape the 2018 midterm elections. Her endorsements included that of Sen. Kirsten Gillibrand (D-N.Y.).

Yet, unlike Raskin, who was able to overcome Trone’s financial advantage, Miller, 53, was largely unknown to many voters in the 6th District, having served two terms as a delegate in Annapolis.

She raised $1.3 million but did not have the money to match Trone on the airwaves.

State Sen. Roger Manno, the Senate majority whip in Annapolis, was endorsed by a number of unions and cast himself as the race’s only authentic progressive. But the $331,000 he raised — including a $72,000 loan from himself — paled in comparison with the resources available to Trone and Miller.

Manno finished fourth, less than 100 votes behind first time candidate, Nadia Hashimi, a pediatrician and author.

The other Democratic candidates — including retired intelligence officer Andrew Duck, retired economist George English, businessman Chris Graves and aerospace executive Christopher Hearsey — were never a factor in the race.

Trone is the latest tycoon to migrate from business to politics, joining a group that includes former New York mayor Michael Bloomberg and Florida Gov. Rick Scott (R).

Trone’s wealth could give him an obvious advantage over Hoeber in November, although her campaign consultant, Paul Ellington, has said she is likely to make Trone’s spending an issue. Hoeber spent $4 million in her race against Delaney in 2016.

The 6th District, which stretches from Montgomery County to western Maryland, tends to lean Democratic, having voted decisively for Hillary Clinton over Donald Trump in 2016, and Barack Obama over Sen. John McCain and former Massachusetts governor Mitt Romney in 2008 and 2012, respectively.

“I don’t regard this race as particularly competitive,” said Stu Rothenberg, a political analyst. “You think of Montgomery County as a place where a moderate Republican can do well, but the reality is that with Trump on the top of the ticket, this will be a terrible cycle for Republicans.”

That said, Republican Dan Bongino came within 2,000 votes of defeating Delaney in 2014, a result that the GOP can underline as it prepares for November.