With a lofty lead, a big grin and a pair of American-flag-printed socks, Provo Mayor John Curtis, a moderate Republican, celebrated his win Tuesday night to become Utah’s newest congressman.

“I pledge to serve the underrepresented,” he said during his victory speech. “That means spending more time in rural Utah. It means if you’re not white, Mormon and male, I am still here for you.”

Curtis trounced an astonishingly well-funded Democrat and a surprise third-party newcomer in the special election. He will serve the final year of former Rep. Jason Chaffetz’s term after the congressman unexpectedly stepped down in June and joined Fox News as a contributor.

The Associated Press called the race within an hour of polls closing as Curtis — with nearly 58 percent of the vote — held onto a roughly 30 percentage point margin ahead of his nearest competitor, Democrat Kathie Allen. The National Republican Congressional Committee rushed to congratulate the mayor for his “top-notch campaign.” And Utah Lt. Gov. Spencer Cox stood by Curtis’ side as he announced his triumph.

DISTRICT 3 SPECIAL ELECTION RESULTS

Joe Buchman, Libertarian • 2.18% popular vote • 2,372 votes

Jason Christensen, Independent American • 1.5% popular vote • 1,633 votes

Jim Bennett, United Utah • 8.88% popular vote • 9,641 votes

John Curtis, Republican • 57.57% popular vote • 62,498 votes

Sean Whalen, unaffiliated • 2.73% popular vote • 2,968 votes

Kathie Allen, Democrat • 27.13% popular vote • 29,449 votes

Even in Salt Lake County, where Democrats are expected to do their best, Curtis had a narrow advantage over Allen, according to unofficial results as of 10 p.m. And he’s so far picked up more than five times the votes in Utah County, which includes about 60 percent of the registered Republicans in the 3rd Congressional District.

The new United Utah Party’s Jim Bennett, son of the late three-term Sen. Bob Bennett, came in third at just under 9 percent and was quick to concede.

“It just became very clear that he has an overwhelming lead,” Bennett said, noting that he’s not sure what he will do next. “I honestly don’t know. My plan was to run as hard as I could for this race.”

Minutes later, Allen, too, called Curtis to offer her congratulations and advice. ”[I] told him I hope he has the courage to stand up to Donald Trump,” she said of her phone call with the mayor.

Allen, a longtime physician and first-time candidate, ran an unprecedented and well-financed campaign, raking in more than $800,000 in the strongly GOP-tilted district. With tears in her eyes, she said there were no regrets but worried about disappointing the people who supported her since she launched her bid in March to oust Chaffetz.

“I feel like I let them down,” she said at her election-night party in Holladay. “I know that I couldn’t bring it home.”

She also slammed the lack of support she got from the national Democratic Party. Allen plans to return to her job serving Utah Transit Authority staff at a private clinic and intends to continue her efforts to reform the partisan way the state’s congressional boundaries are drawn.

At the Curtis party, it was all smiles and cheers beginning with the earliest results of the evening at 8 p.m. that put the mayor ahead and rivaled his leads in every poll prior to the election. He could be sworn in as early as Monday, Cox said, to join Utah’s all-GOP federal delegation.

“We did it,” Curtis shouted. “We did it.”

The race had been largely consumed by discussion of President Donald Trump, who has overwhelmed all political topics for the past year including dominating every debate for the open 3rd District seat.

Although he wrote in a “good friend’s name” instead of voting for Trump last year, Curtis wants the president to be successful and intends to work with the administration when he agrees with it. The mayor has maintained that he supports the Trump agenda on economics, taxes and defense while he ignores the president’s “distractions.”

“A lot of people are wanting me to be Trump-like, and I’m not going to be,” he has said.

Curtis ran a shooting range business in Provo before serving two terms as mayor of the state’s third largest city and one of the most conservative in the nation.

After winning a gritty three-way Republican primary in August where he was criticized for not being conservative enough (and for once being a Democrat some 20 years ago), Curtis faced pushback during the general election for using the president’s slogans, such as “drain the swamp,” in campaign advertising and removing a post on Facebook exhorting Congress to “build the wall” between the United States and Mexico.

Still, he’s considered a moderate candidate, launching his bid by collecting voter signatures instead of relying on ultraconservative GOP convention delegates.

During the campaign, he captured support from Utah Gov. Gary Herbert, former Republican presidential nominee Mitt Romney, U.S. House Majority Leader Kevin McCarthy and Chaffetz. House Speaker Paul Ryan congratulated Curtis on Tuesday, saying he will be a “valuable addition” to the Republican conference currently looking to advance tax reform.

Mary Swenson, of Cottonwood Heights, did not vote for Trump last year but cast her ballot for Curtis on Tuesday calling him the “more middle-of-the-road” choice.

“What I really want is someone who can see beyond party lines,” she added.

Both Allen and Bennett built their campaigns on standing against Trump, distancing themselves from most of his policies and rhetoric. “The best way to defeat the Trump agenda,” read, in part, a mailer sent out by Allen, “is to vote for a commonsense Democrat.”

Sue Villani, a Cottonwood Heights resident the same as Allen, voted for the doctor while suggesting “this is a godawful place for progressives.” Ahren Exeter also cast her ballot for Allen, saying Trump played a big part in the decision.

“I think it influences everyone’s vote,” she said. “I want change — big time.”

Bennett was a Republican but left the party when Trump was nominated in the 2016 presidential race. He’s billed himself as an “honest broker” between the two major parties. He anticipated running in 2018, but launched a bid after Chaffetz’ early departure turned what would have been a municipal primary only into a complicated congressional special election — the first in Utah in 90 years.

The other third-party and independent candidates, including Libertarian Joe Buchman, collected less than 7 percent of the vote.

The 3rd Congressional District, where registered Republican voters outnumber Democrats nearly six to one, stretches from central Salt Lake County to the southernmost border of San Juan County.

Curtis, standing in front of an American flag, highlighted that landscape and promised to represent the more than 700,000 constituents within.

“I am committed to waking up each morning and caring about every one of you. Those who know me best know that it doesn’t matter if you’re 9 or 90, rich or poor, gay or straight, Mormon or atheist, Navajo or Caucasian,” he said. “I work for you, and you’re my boss.”

-Tribune reporters Taylor W. Anderson and Jennifer Dobner contributed to this story.