Speaker Emerita Nancy Pelosi is backing Supervisor Connie Chan for Congress.

The endorsement, long anticipated by political insiders, could reshape a competitive race to fill the seat Pelosi has held for four decades. Chan, who has trailed state Sen. Scott Wiener in polls, now has the most powerful name in San Francisco politics in her corner heading into the June primary.

The announcement will come in a video scheduled for release Tuesday.

“I have been watching this race closely with all of you — and I believe one candidate stands above the rest,” Pelosi says in the recording. “Connie Chan is the leader best prepared to carry forward the fight for San Francisco in the Congress of the United States.”

Pelosi touts Chan’s time on the Board of Supervisors budget committee, fighting for working-class families, and her protection of San Franciscans from federal healthcare cuts.

Wiener is considered the front-runner in the race, with polls showing Chan and Saikat Chakrabarti vying for second place.

For months, Pelosi has flirted with the idea of an endorsement, appearing at a fundraiser for Chan in D.C. and allowing her to use her photo in campaign materials.

While Chakrabarti and Chan both tout their progressive Democrat leanings, Chan enjoys support from the left flank of organized labor and most local progressive Democratic groups, whereas Chakrabarti’s support comes mostly from outside San Francisco.

Chakrabarti has struggled to gain high-profile endorsements, as Rep. Alexandria Ocasio-Cortez, his former boss, has stayed silent on the race.

Sam Lauter, a principal (opens in new tab) at public affairs and political consulting firm BMWL, said Pelosi’s endorsement may make the difference, as Chan and Chakrabarti have polled closely together.

“In a very close race for second place, everything helps,” he said.

He thinks Pelosi’s endorsement would come into play especially in a one-on-one matchup with Wiener.

“I think it would make a significant difference,” Lauter said. “It would make it a real race.”

Still, Lauter cautioned, the state senator is a formidable foe, and progressive candidates like Chan often struggle in citywide races against moderate Democrats like Wiener.

Pelosi said Chan, an immigrant from Hong Kong who grew up in San Francisco, would bring needed experience to Congress during a time of turmoil for immigrants. Chan has said she wants “full accountability” for federal officials who violate immigrants’ rights to due process.

She supports Medicare for All, believes the federal government should play a stronger role in investing in public housing, and pledged to cosponsor the Richard L. Trumka Protecting the Right to Organize Act (opens in new tab), (opens in new tab) which would strengthen workers’ rights to unionize. Pelosi also backed Chan’s 2024 supervisor race.

“Connie Chan has the experience, the values, and the determination to do just that. I know this district, I know the Congress, and I know Connie. I’m proud to endorse Connie Chan, and I ask you to join me in electing her to Congress,” Pelosi said.