Kate Snyder was elected Portland’s next mayor Tuesday, unseating the incumbent and defeating a sitting city councilor.

Mayor Ethan Strimling and City Councilor Spencer Thibodeau both conceded defeat when it became clear Snyder would prevail.

Although Snyder’s lead after the first round of vote counting appeared insurmountable, her victory wasn’t officially decided until after a late-night runoff in which votes for the two candidates with the least votes were redistributed according to the voters’ second choices. The process ended just before midnight when Snyder topped the 50 percent threshold  and was declared the winner.

Snyder, a former school board chair who runs a nonprofit that supports education in the city, collected 39 percent of the votes in the first round. Thibodeau and Strimling followed with 28 percent and 25 percent, respectively. Travis Curran finished with 7 percent of the vote.

After both Curran and Strimling were eliminated during the runoff, Snyder finished with 62 percent of the votes and Thibodeau trailed with 38 percent.

Snyder celebrated her lead with jubilant supporters but did not claim victory after the first round. “Nothing is absolutely final yet, but I do think things are looking pretty good,” a visibly excited Snyder said. Snyder thanked Strimling for serving as mayor and said she looked forward to working with Councilor Thibodeau before she and her supporters went home to wait for final results of the runoff.

Portland mayor Ethan Strimling talks to voters about his re-election bid outside the polling location at the Italian Heritage Center on Election Day. Ben McCanna/Staff Photographer Buy this Photo

Strimling delivered his concession speech shortly after 9 p.m. in front of supporters gathered at Maine Craft Distilling on Washington Avenue.

“Let me just say, we have a tremendous amount to be proud of,” he said. “The four years of work we have achieved, rebuilding our elementary schools, banning pesticides in the city of Portland, building affordable housing, providing property tax relief for seniors, increasing wages for workers in the city. These are all things that will be a legacy for us to remember in terms of what this city can be and I hope we will continue the fight.”

In an interview after his speech, Strimling said his re-election bid was an uphill battle. “Sometimes when you push as hard as we pushed to try to get some pretty important results, there’s some serious pushback and that’s what happened.”

Snyder’s supporters gathered at Salvage, a barbecue restaurant on Congress Street, and cheered as the results came in and Strimling conceded.  Snyder traded high-fives with supporters amid chants of  “Kate, Kate, Kate!”

Thibodeau, who watched results come in with supporters at the Little Tap House on Spring Street, conceded shortly after 10 p.m.

“This started about 9 months ago right here and tonight it comes to an end here,” he said. “I’m just so absolutely humbled by this experience, and so humbled to have this experience with you. This is not the end. This is the beginning. We knew desperately that we needed new leadership. I would have hoped it was me, but I’m hopeful because it’s Kate.”

This was the third contest since 2010, when the position was changed from a part-time ceremonial mayor selected each year by the City Council to a full-time position elected by voters citywide. The mayor gets a four-year term and a salary, which is now $76,615 a year, although city government operations are still run by the professional city manager.

Snyder is the first woman to win the elected mayor position since it was created, but numerous women served as mayor when the post was appointed by the council.

The unpredictability of the race fueled a strong voter turnout in the city for an off-year election. About 30 percent of Portland voters cast ballots Tuesday, while the statewide voter turnout was expected to be between 10 and 20 percent.

North Deering resident Mira D’Amato, 21, declined to explain how she ranked the mayoral candidates on the ballot she cast at the Grace Baptist Church. But she and her mother, Terry, 42, both suggested that Strimling was not their first choice.

“I think it’s time for a change in leadership,” Mira D’Amato said, noting that she was concerned about education and affordable housing. “Not enough has been accomplished with housing, so hopefully some new leadership will make progress on that.”

Portland mayoral candidate Travis Curran talks to voter Chad Rasmussen outside the polling location at East End Elementary School on Tuesday afternoon. Ben McCanna/Staff Photographer  Buy this Photo

Riverton resident Nicole Myers, 46, said she marked Snyder first on her ballot and Thibodeau second. As a mother and educator, she appreciated Snyder’s previous service on the school board and her current role as the head of the Foundation for Portland Public Schools, which raises private funding to help support education.

“I really like how she’s looking for other revenue sources, rather than just relying on property taxes,” Myers said, adding that Snyder was “pragmatic, honest and transparent” about what the city can and can’t accomplish.

At the Italian Heritage Center in District 3, several voters said they marked Thibodeau first.

Rosemont resident Julia Ridge, 60, said she doesn’t like the “vitriol” of local politics in recent years, so she marked Thibodeau first. “He supports a lot of the things I support,” she said. “And he seems to get what the mayor’s position is supposed to be.”

Libbytown resident Starr Soul-McDonald, 31, also marked Thibodeau first and “not Ethan” second. “We need something different,” she said. “I want to see what he can bring to the table.”

Kate Snyder, the eventual winner, shakes hands with voter Jim Willey outside the polling station at the Italian Heritage Center on Election Day.Ben McCanna/Staff Photographer Buy this Photo

But Libbytown resident Logan Kendzierski-MacDonald, 24, said he was sticking with Strimling, because of his support of immigrants. “I like what he’s done keeping Portland a safe place for refugees,” he said.

The ballots were cast after a long and heated campaign during which candidates raised record sums of money and debated the role of the mayor.

Snyder, 49, emerged as a formidable challenger after stepping back into city politics after a six-year hiatus. She pointed to her experience leading the school board during the Great Recession and as a homeowner who put her three kids through public schools. She campaigned on balancing political ambition with financial capacity, focusing largely on the decision-making process as opposed big ideas, though she advocated for rezoning industrial areas to allow for housing.

Strimling, 52, defined his candidacy as the most progressive in the race, racking up endorsements from 31 labor unions and progressive activists, including national nods from The People for Bernie and The Progressive Change Champion Committee. He vowed to “push through” a $15 minimum for Portland businesses, enact tenant protections previously turned down by the council and advocate for a local $10 million to build more affordable housing.

Both Thibodeau and Snyder promised to end the division that marked Strimling’s first term and pit the mayor against the council and the city manager – something they argued was holding the back from making progress on pressing issues like affordability and affordable housing.

Thibodeau, 31, pointed to endorsements from five sitting councilors and his four years of working with City Manager Jon Jennings as proof of his readiness to hold the city’s highest elected municipal office.

Portland mayoral candidate Spencer Thibodeau greets voters outside the polling station at St. Pius X Church on Election Day. Thibodeau finished second in the four-way race. Ben McCanna/Staff Photographer Buy this Photo

Curran, meanwhile, challenged Strimling over who would truly represent the “voice of the people.” The 33-year-old waiter at Empire Chinese Kitchen argued that he could better relate to the existential anxiety of artists and those in the service industry who worry about being priced out of Portland amid a development boon of luxury condos and hotels.

The race also included the involvement of outside groups, which traded ethics complaints that have not yet been acted upon by the state Ethics Commission.

The biggest spending came from the Unite Portland political action committee, which was formed by Strimling’s former campaign treasurer Dory Ann Waxman with the stated purpose of opposing Strimling’s re-election, while not supporting any specific candidate. The group spent over $30,000, primarily on web videos and Facebook ads. The involvement of Lance Dutson, a well-known Republican political operative, became fundraising fodder for the incumbent.

Progressive Portland, a social welfare nonprofit founded by West End resident Steven Biel, helped Strimling raise money and organize field operations. And a political action committee run by Strimling’s former assistant mayor, Jason Shedlock, executive director of the Maine State Building and Construction Trades, took out some last-minute newspaper ads in support of the incumbent.

The Strimling campaign filed two ethics complaints against Unite Portland, the most substantial of which was over its failure to report independent expenditures. Waxman returned the favor, filing a complaint over the Strimling campaigns failure to report help from Biel and Progressive Portland as contributions.

Although the commission has yet to weigh in, staff issued a preliminary analysis indicating that Waxman did not offer enough evidence to substantiate her claim, while also suggesting that Unite Portland could be fined $7,000 over issues brought to light by Strimling’s campaign.