A super PAC backing London Breed’s campaign for mayor went live with its first attack ad over the weekend, an ominous campaign spot that accuses opponent Mark Leno’s backers of forcing Breed out of the mayor’s office through backroom deals, “all because they had their power threatened by her.”

The ad — funded by “S.F. Women Supporting London Breed for Mayor” — opens with a picture of Breed, who became acting mayor upon the December death of Mayor Ed Lee, marching at the Jan. 20 Women’s March. With Breed leading a contingent, the female narrator said, “it felt like it was finally our time.”

It then cuts to a black-and-white picture of Supervisor Aaron Peskin, who is widely credited with — or blamed for, depending on your perspective — putting together the six board votes needed to replace Breed with former Supervisor Mark Farrell. The narrator says “this guy” — meaning Peskin — “cut a backroom deal” with “these guys — meaning Supervisor Jeff Sheehy and Farrell — “to help this guy,” meaning Leno.

“Sound familiar, ladies?” the narrator adds.

The ad prompted a swift rebuke from Leno, who has asked all candidates in the race to sign on to a fair campaign pledge to “publicly denounce, renounce and reject” independent expenditure funds spent on their campaigns by outside parties.

Leno said “disgusting special-interest super PACs are no way to run a campaign.” He called on the Breed campaign to “reveal the donors” behind the ad, adding that “this is dark money until the donors are revealed.”

“Let the campaign attack me — why do we need outside super PACs?” he said.

Breed campaign manager Maggie Muir said, “None of us have any control over any PACs,” and said the campaign “denounces any campaigns, independent or otherwise, that attack any candidates in this race.”

Asked if the Breed campaign specifically denounced the “S.F. Women” ad, Muir stated, “Our statement speaks for itself.”

“We will not tell women to shut up and sit down, but we have nothing to do with this ad,” she said. “We’re focused on our own campaign, our own candidate, our own message.”

In addition to Leno, the fair- campaign pledge has been signed by candidate and Supervisor Jane Kim and candidate Amy Farah Weiss.

— J.K. Dineen

Email: cityinsider@sfchronicle.com, jdineen@sfchronicle.com Twitter: @sfcityinsider @sfjkdineen

Campaign ad

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