“We’re ready to be a Boston that doesn’t push people out, that welcomes all who call our city home,” Wu told hundreds of jubilant supporters after her rival, moderate City Councilor Annissa Essaibi George, called her to concede. “We’re ready to be a Boston where all can afford to stay and to thrive. And yes, Boston is ready to become a Green New Deal city.”

But the win was one of the few bright spots for progressives in an otherwise lackluster night for the left — and the Democratic Party.

Buffalo, N.Y., mayoral candidate and Democratic socialist India Walton appeared to lose her race to an unusual write-in candidate: Democratic incumbent Mayor Byron Brown, who declared victory Tuesday night. Walton refused to concede as returns showed her far behind votes cast for write-in candidates.

“Today’s election was not just a referendum on the city of Buffalo, it was a referendum on the future of our democracy and our vision for our future,” Brown said in his victory speech.

Walton’s loss is a blow not only to the insurgent left — she was backed by Rep. Alexandria Ocasio-Cortez, former congressional hopeful Nina Turner and the Working Families Party, which poured nearly half a million dollars into her election effort in October alone — but to establishment Democrats as well. Senate Majority Leader Chuck Schumer and Sen. Kirsten Gillibrand (D-N.Y.) put their political might behind Walton in the race’s final weeks.

Moderates added more wins to their column from incumbent Mayor Jacob Frey in Minneapolis and Eric Adams in New York. Adams, who will replace Bill de Blasio in January, beat his Republican challenger by almost 40 points Tuesday, nearly four months after emerging from a crowded primary and labeling himself the “face of the new Democratic Party.”

Seattle’s moderate mayoral candidate Bruce Harrell finished with more than 60 percent of the vote. And Miami Mayor Francis Suarez was reelected to a second term, joining the ranks of the handful of Republican mayors leading big cities.

And in addition to Frey’s victory in Minneapolis, a ballot initiative that would reshape the city’s police department and replace it with a department of public safety was defeated 44 percent to 56 percent. Both Frey’s win and the defeat of the initiatives marked significant setbacks to one wing of the police reform movement.

In an interview before Tuesday’s election, Sheila Nezhad, the foremost progressive challenger to Frey, said the city’s ballot amendment — also known as Yes 4 Minneapolis — gave the city’s residents “an opportunity to lead in terms of policing and public safety right now. And take steps towards building a better system.” She and several other organizers who led protests against police violence in Minneapolis last summer mounted challenges to Frey.

Still, progressives made some inroads on the policy level. Minneapolis’ charter amendment to establish rent control passed. In Cleveland, an initiative that would establish a civilian review board for the city’s police division passed 41 percent to 59 percent. And Austin, Texas, voters defeated a pro-police ballot amendment that established a minimum number of police officers in the city.

The results are reflective of a slow but recognizable sea change in city politics following last summer’s protests against police violence and systemic racism, said Atima Omara, a Virginia-based political consultant and former senior adviser to Boston mayoral candidate Andrea Campbell.

“How are citizens in our country over a year and a half later now looking at criminal justice reform and public safety in their cities?” Omara said. “It’s not that there won't continue to be advocates, but what is going to be the electoral will, based off what happens in cities across the country?”