Initial fundraising reports from the first week of Matt Mahan’s gubernatorial campaign filed Tuesday reveal the depth of support for the moderate Democrat from Silicon Valley executives and venture capitalists.
Reports filed with the California Secretary of State show just 21 individuals contributed more than $1.6 million to Matt Mahan for Governor 2026 in the first two days of his campaign. The more than $2 million in contributions reported in this week’s filings are part of more than $7 million that Mahan said Saturday was donated to his campaign in its first week, and includes only those who contributed $5,000 or more.
The 43-year-old second-term mayor of San Jose announced his candidacy Jan.29.
An independent expenditure committee formed to boost the Mahan campaign said last weekend it had raised more than $3.2 million and spent $1.5 million on a Super Bowl ad.
Deep pockets of Big Tech millionaires are likely to be critical to Mahan’s “Back to Basics” campaign if he is to emerge as one of two finalists out of the June 4 primary.
There are no limits to what individuals can contribute to independent expenditure committees, which are required to be separate from candidate-run campaigns. Direct contributions to a gubernatorial candidate are limited to $39,200 for the primary and $39,200 for the general election.
The independent committee said last weekend that its contributors included Y Combinator partner Michael Seibel, Riot Games co-founder Marc Merrill, Bay Area venture capitalists Neil Mehta and Brian Singerman and investor Paul Wachter, without disclosing amounts.
Y Combinator CEO Garry Tan was among 21 individuals listed as double contributors – giving $39,200 for both the primary and general election in direct payments to the Mahan campaign. Seibel also was listed for a similar double contribution to the campaign, in addition to his support for the independent committee.
Other $78,400 contributors to the Mahan campaign last week included: Alphabet co-founder Sergey Brin; Future Ventures founder Steve Jurvetson along with $78,400 in contributions from Genevieve Jurvetson of the Jurvetson Foundation; Amazon Ring’s inventor Jamie Siminoff; Roblox CEO David Baszucki and Baszucki Group president Jan Baszucki; Cloud Kitchen co-founder Diego Berdakin; Github co-founder Chris Wanstrath and Nina Wanstrath; Byers Capital managing partner Blake Byers; Devcon Construction president Gary Filizetti; Quiet Capital’s Brian Singerman; Lightspark Group CEO David Marcus; Caruso Management’s Rich Caruso; venture capitalist Jeremy Liew; Bot Company CEO Kyle Vogt.
Mahan’s first-week contributions – direct and indirect – dwarfed all other governor candidates, not just for 2026, but for all of 2025, except former presidential candidates and billionaire environmental activist Tom Steyer.
Steyer, also running as a Democrat, is dipping into his personal fortune for all but $80,000 of his 2025-26 contributions. He reported contributing nearly $9.3 million in the first month of 2026 after contributing $28.9 million (and spending $27.4 million) in 2025.
Here is a summary of the latest fundraising by the campaign committees of other major governor candidates (the 2026 numbers reflect just contributions over $5,000): Katie Porter raised $6 million in 2025, spent nearly $2 million, raised nearly $120,000 in 2026; Steve Hilton raised $5.7 million in 2025, spent $3.9 million and reported just under $170,000 in 2026 contributions; Antonio Villaraigosa raised $3.2 million in 2025, spent $2.5 million, raised just over $153,000 in 2026; Eric Swallwell raised $3.1 million, spent $634,000, raised just under $120,000 in 2026; Betty Yee raised $593,000 in 2025, spent $704,000 and collected just $5,000 in 2026; Tony Thurmond raised $251,000 in 2025, spent $457,000, and collected just $5,000 in 2026; Ian Calderon raised $303,000, spent $495,000 in 2026.
