Congressional candidates William D. Euille, left, and Don Beyer, with Ann O'Hanlon, who works with Beyer, chat outside the Durant Memorial Center as Virginia voters go to the polls in the state’s 8th District to choose a Democratic nominee. (Jahi Chikwendiu/The Washington Post)

Former Virginia lieutenant governor Don Beyer on Tuesday decisively won the Democratic nomination for the congressional seat being vacated by Rep. James P. Moran (D), beating the next-closest candidate by more than 2 to 1.

With all of the votes counted, Beyer captured 45.8 percent of the ballots. As a Democrat, he is heavily favored to win the general election in November.

“The heart of my message was: Proven,” Beyer, 63, said in a telephone interview from his victory party in Alexandria, where Gov. Terry McAuliffe (D) had just walked in. “We needed a congressman with a broad range and depth of experience. . . . I blended it with very clear and strong policy positions on guns, climate change, income and wealth inequality and women’s right to choose.”

Del. Patrick A. Hope (Arlington) came in second, with 18 percent of the vote. State Sen. Adam P. Ebbin (Alexandria) took third, with 14 percent, followed by Alexandria Mayor William D. Euille at 8 percent, talk show host Mark Levine at 7 percent, former Northern Virginia Urban League leader Lavern Chatman at 5 percent and Virginia Tech professor Derek Hyra at just over 1 percent.

[See the results of all of Tuesday’s primaries here.]

In a low-turnout election with a crowded field, Beyer, a former ambassador and fundraiser for President Obama, swept all four jurisdictions represented by the 8th District. He took more than 70 percent of the vote in Falls Church, the site of the first of his family’s nine auto dealerships, more than 50 percent of the vote in Fairfax County, 44 percent in Alexandria and more than 39 percent in Arlington County.

“I voted for Beyer because he’s a good liberal Democrat, he supported Howard Dean and supported President Obama,” said Theresa Cummins, of Arlington. “I’ve known him for a long time. His record has always been very good — I don’t know these other people.”

Beyer will face Republican Micah Edmond and several third-party candidates in November. Despite the Democratic Party’s dominance in this part of the state, Beyer said he will not take the general election campaign for granted. If elected in November, he said, he hopes to serve 12 to 20 years.

“I’m a young man,” he quipped.

Earlier in the day, Beyer ran into Euille, his mayor, at the Durant Memorial Center, where they both cast their ballots.

“I’ve voted for him many times,” Beyer said after the two men shook hands.

“And I’ve voted for him many times, when he was running for lieutenant governor and governor,” Euille replied.

“But,” Beyer said, laughing, “I’m not voting for him today.”

Virginia’s 8th District, one of the wealthiest and most educated in the nation, is populated by many federal government employees and contractors. Thirteen candidates had originally announced their intentions to run in the primary, but by Tuesday, only seven remained. The retirement of Moran, a 12-term veteran, means the liberal enclave is losing congressional seniority and clout.

Beyer, who was Obama’s Mid-Atlantic finance chairman in 2008, raised more than $1.1 million in campaign funds, far more than any of the other candidates. Obama appointed Beyer ambassador to Switzerland and Liechtenstein in 2009, and Beyer called on his contacts from the Obama administration for endorsements.

In addition, the Beyer family’s auto dealerships gave him name recognition outside the world of politics.

Dennis Scanlon hobbled into his polling place in Arlington on crutches, just four hours after having foot surgery at a hospital. He voted for Beyer, he said, because “he’ll be the strongest coalition builder.”

“I was in Afghanistan a year ago,” Scanlon said. “I know what a vote is worth.”

Morris and Sandra Peterson, who moved to Arlington from Minnesota decades ago, said they voted for Hope because they trusted his liberal Democratic values.

“I read his literature, and he said he’s a Hubert Humphrey Democrat,” said Morris Peterson, who voted at the Woodmont Center in Arlington on Tuesday afternoon. “It was hard to choose. I’m not certain Beyer has done enough in Northern Virginia lately.”

Rita Sollod said she, too, had a hard time choosing, finally bringing her options down to Beyer or Levine. “I heard his ads, and they inspired me,” she said of Levine, who dubbed himself “the aggressive progressive.”

Ebbin’s work in Richmond won the vote of Jim Carey, 63, of Alexandria, even as Carey acknowledged that he did not expect Ebbin to win. His accomplishments, like those of other candidates, were overshadowed, Carey said, by the massive volume of ads and campaign literature produced by Beyer’s campaign.

At Westgate Elementary School in Falls Church, Sandy Kiersz, 41, said she voted for Chatman in hopes of seeing another woman in Congress.

“I don’t feel women’s voices are heard as much as they should be,” she said, adding that in a district firmly held by Moran for so many years, she was glad to see new faces competing for the seat.