MARY LOUISE KELLY, HOST:

In San Francisco, the unexpected death of Mayor Ed Lee in December has set off a hard-fought campaign to succeed him. As Scott Shafer from member station KQED reports, the contest shines a bright light on that city's racial and economic divides.

SCOTT SHAFER, BYLINE: The morning Mayor Lee died, London Breed, the 43-year-old president of the board of supervisors, automatically became acting mayor.

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LONDON BREED: And I ask for your patience. And I ask for your support. And I ask for your prayers.

SHAFER: Breed is a native San Franciscan who grew up in one of the city's toughest public housing projects. By San Francisco standards, Breed is seen as a moderate and somewhat business-friendly. And that didn't sit well with liberals who felt her new high profile was giving her an unfair advantage in the race for mayor. The supervisors had to decide whether to keep Breed on or replace her with a caretaker mayor until the June election. That led to dozens of people like Brad Chapin testifying in support of Breed...

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BRAD CHAPIN: I think that we absolutely must have a woman of color be our acting mayor or appointed mayor.

SHAFER: ...And opposing her, like supervisor Hillary Ronen, who said Breed is in the pocket of wealthy tech moguls.

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HILLARY RONEN: They are threatening people if they don't support London Breed. They are saying that people's careers will be ruined if they don't support London Breed.

SHAFER: After a raucous debate, the supervisors voted to replace Breed with another supervisor, Mark Farrell, a white former venture capitalist who represents some of the city's wealthiest neighborhoods. Breed's supporters, especially African-American women, were furious.

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UNIDENTIFIED WOMAN: (Chanting) Shame on you. Shame on you. Shame...

SHAFER: The whole episode has reopened painful wounds in San Francisco.

JAMES TAYLOR: It's almost like these white liberals are undermining the black woman mayor on behalf of the black community.

SHAFER: James Taylor teaches political science at the University of San Francisco.

TAYLOR: You can talk to most older African-American San Franciscans. And if you mention redevelopment, they will tell you it was - urban renewal was Negro removal. That sentiment has carried over for 40 years.

SHAFER: As African-Americans have left the city, the Asian-American and Latino populations have grown. But they, too, now feel the economic squeeze. City supervisor Jeff Sheehy, who cast the deciding vote to replace London Breed, puts it this way.

JEFF SHEEHY: Everything that made us so attractive that we became the boom place for tech - it was our tolerance, our values, our diversity. The people who built that are being pushed out.

SHAFER: Among the candidates running for mayor besides Breed are another supervisor who is an Asian-American woman and an openly gay man who's a former state senator. City supervisor Malia Cohen says the whole controversy is a distraction.

MALIA COHEN: We should be coming together to talk about homelessness and car break-ins and many of the issues that are at the forefront of people's minds. But now race, gender and sexual orientation are going to be at the forefront.

SHAFER: Competing no doubt with the pressing issue of income inequality and the cost of living in San Francisco. But there is an upside to this political skirmish, says David Lee, who's active in the city's Asian-American community.

DAVID LEE: I think people are deeply invested in this election in a way that I haven't seen before. And for the first time in a long time, we're going to have a really open election.

SHAFER: Whoever wins in June will serve only the rest of the late mayor's term, so next year voters will once again decide who should lead this city for another four years. For NPR News, I'm Scott Shafer in San Francisco.

[POST-BROADCAST CLARIFICATION: In this report, we say Brad Chapin was among dozens of people testifying in support of London Breed, San Francisco’s acting mayor. As Chapin said at a public meeting, he believes the acting or appointed mayor should be a woman of color such as Breed. But his preferred candidate for mayor in the June election is a different city supervisor, Jane Kim.] Transcript provided by NPR, Copyright NPR.