Matt Mahan’s floundering campaign for California governor has been hit with a new bombshell complaint accusing the San Jose mayor of illegally coordinating with a billionaire-funded PAC — and the allegations could warrant penalties up to $5 million.
The Post exclusively obtained the complaint, which accuses Mahan and an independent expenditure committee called Back to Basics of violating state election law on coordination by using same polling company, Impact Research, and each paying the firm $89,500.
Allegations made to the state’s Fair Political Practices Commission note that similar sharing of “key strategists” has resulted in major fines in the past, and Mahan’s indiscretions could trigger penalties in the millions.
Political experts told The Post that Mahan’s use of the same polling firm as the pro-Mahan committee was unprecedented, “sloppy” and “unseemly.”
Mahan, who is polling in sixth place, has been in a free-fall this week, as billionaire donors like Netflix co-founder Reed Hastings — who clawed back $1 million from the pro-Mahan committee — are jumping ship.
Other billionaire backers to the pro-Mahan committee have included venture capitalist Michael Moritz, Los Angeles businessman Rick Caruso and Stripe CEO Patrick Collision.
The complaint could carry massive consequences because California Back to Basics has already raised and spent more than $23 million supporting Mahan’s gubernatorial campaign, which has reportedly led to him missing more than third of San Jose city council meetings since he launched his campaign in January.
If regulators determine the IE committee coordinated with the campaign through the use of “shared key strategists,” those expenditures could potentially be reclassified as illegal in-kind campaign contributions.
“This has the potential to be one of the largest enforcement actions in FPPC history,” the complaint states.
The complaint marks the second time Mahan and the Back to Basics committee have been accused of illegal coordination in a formal complaint to the state’s Fair Political Practices Commision.
David Latterman, a longtime political analyst in San Francisco who spent nearly two decades working on campaign polling operations, called the new allegations “unseemly” and unprecedented.
“I think there are legs to the complaint,” Latterman said.
“They’ve put themselves in a position where it looks like collusion,” Latterman said. “You still have to prove it, but I can’t even think of a time where I’ve heard of this happening before.”
Candidate committees are bound by more restrictions than independent committees that can raise unlimited sums of money. Among the PAC’s biggest donors was Moritz, the influential former Sequoia Capital chairman, who contributed roughly $3 million combined.
Caruso kicked in at least $1.25 million through direct and affiliated donations, while Reddit CEO Steve Huffman gave nearly $1 million, and Collison contributed roughly $1.49 million across multiple donations.
Campaign finance filings cited in the complaint show the PAC paid Impact Research $89,500 in February 2026 for polling and strategic consulting services. Mahan’s campaign later paid the same firm another $89,500 in April.
Impact Research has previously done polling for Presidents Barack Obama and Joe Biden, as well as Hillary Clinton’s campaign for president.
The complaint also points to campaign press releases and media reports publicly identifying Impact Research as Mahan’s pollster. It alleges the firm’s work involved strategic polling, message testing and voter modeling — core campaign functions that can trigger coordination concerns under California law.
Michael Trujillo, a political consultant for Antonio Villaraigosa who filed the previous FPPC complaint against Mahan over allegedly illegal coordination with the Back to Basics committee, said the overlapping polling arrangement is “more than just sloppy — it’s plain dumb and stupid.”
“It goes to the arrogance of Silicon Valley thinking they don’t have to play by the rules and break everything,” Trujillo said.
“And that mentality doesn’t work when there are clear lines regarding the law.”
The filing further alleges the timing of a multimillion-dollar ad blitz by the PAC aligned closely with an April internal poll conducted for Mahan’s campaign. It also cites a PAC memo referencing “a massive voter contact effort” involving both the campaign and Back to Basics.
Officials for the Mahan campaign and Back to Basics were unaware of the complaint when contacted by The Post, and neither immediately responded to requests for comment. Impact Research also did not respond to a request for comment.
