Why Matt Mahan’s late entry reshapes California’s governor’s race

It wasn’t a field-clearing name like former Vice President Kamala Harris or Attorney General Rob Bonta. But the mayor of the state’s third-largest city has shaken up the most wide-open California governor’s race in decades.

Political experts said San Jose Mayor Matt Mahan’s entrance into the race last week likely will force a reckoning among fellow Democrats and their donors about nudging some of their now nine contending candidates to step aside to avoid splitting their votes so much that Republicans finish in the top two and advance to November. Other Democrats will have to adjust their messaging to counter a new threat.

“Mahan upsets the race,” said David McCuan, a political science professor at Sonoma State University. “He gets attacked by each side, and he also at the same time puts pressure on the single-digit candidates to get out.”

As Democratic Gov. Gavin Newsom terms out after eight years in office, the Democrats vying to succeed him in a state their party has fully controlled have struggled to catch fire in polling.

Republicans see an opening to return to relevance with the state plagued by high housing costs, homelessness, skyrocketing energy rates and a growing budget deficit, but face headwinds from President Donald Trump’s unpopularity with most California voters.

With upward of 30% of voters still undecided, according to recent independent polling, the race to the June 2 primary, where the top two candidates will move on, is still anybody’s game, putting a large chunk of voters in play for candidates regardless of party.

Other contending Democrats include former Rep. Katie Porter, Rep. Eric Swalwell, former health secretary and Attorney General Xavier Becerra, former Los Angeles Mayor Antonio Villaraigosa, investor and environmental advocate Tom Steyer, state Superintendent of Public Instruction Tony Thurmond, former state Controller Betty Yee and former Assemblyman Ian Calderon.

With the California Democratic Party’s annual convention being held in San Francisco later this month, McCuan expects some “hard conversations” about what’s best for the party.

Mahan entering the fray raises concerns among Democrats that their vote will be further divided, giving former Fox News host Steve Hilton and Riverside County Sheriff Chad Bianco — both Republicans — a better chance of reaching the general election.

Businessman Stephen Cloobeck was the last Democrat to drop out of the race in November when he bowed out to make way for Swalwell. Now, with five months to go and Mahan adding to the field, McCuan expects the number of candidates to shrink again.

“There needs to be a plan for consolidation,” McCuan said. “Everyone’s for competition until it starts to hurt the party.”

McCuan said based on polling, candidates like Thurmond and Yee with support in the low single digits may be nearing the end of their viability.

It’s too early to tell which Democrats Mahan’s announcement will have the greatest impact on. Because of the large field and the number of undecided voters, several political observers said that support for many candidates is still pretty soft, making voters’ decision especially malleable.

Bill Whalen, a former GOP strategist, said that he doesn’t see Mahan, a moderate who comes from the tech-sector, being able to pick off votes from either of the Republican candidates.

“I know that’s been the thinking of the open primary all along, that voters will make these calculated Machiavellian choices: ‘Well I’ll vote for a Democrat I could live with over a Republican who doesn’t have a chance in November,’” Whalen said. “But it doesn’t seem to work out that way.”

Hilton, who met with Mahan in San Jose last month for a tour of one of the city’s interim housing communities, assailed the mayor’s decision to run in a social media post, criticizing him for being in favor of “Democrats’ climate change insanity.”

The two were previously in agreement over Mahan’s strategy to invest in building shelters over permanent support housing to address the homeless crisis.

Whalen said that Mahan’s entrance in the race could also cause Steyer, who ran for president in 2020, to “rethink his spending.”

Steyer and Mahan are “in the same lane,” according to Whalen, pitting the mayor against a well-funded rival.

They’ve both been critical of the Sacramento establishment and have cast themselves as “not part of the status quo.” Some of Steyer’s ads have also focused on getting “back to basics,” which has been Mahan’s key policy platform in San Jose.

“Is Steyer going to spend money trying to take Matt Mahan or not, or is he going to spend his money building himself up, or does he have so much money that he can do both at the same time?” Whalen said.

Steyer’s team quickly jumped to make a statement on Mahan’s candidacy last week that appeared to take aim at Mahan’s opposition of a proposed wealth tax on the state’s billionaires that many in the technology world oppose. Steyer, a billionaire himself, has said the state’s wealthiest residents and cooperations should pay more in taxes.

“The race for California’s future is coming into focus: Californians will choose between a government captured by wealthy interests and corporations raking in record profits, or one that stands with working people and demands fairness and shared responsibility,” spokesperson Kevin Liao said in the statement. “Tom Steyer will continue to make the case that billionaires and wealthy corporations should pay their fair share.”

Steyer has enough wealth to stay in the game. And Villaraigosa — who like Mahan has mayoral experience and similar practical, problem-solving messaging, has signaled he won’t leave.

Terry Christensen, a San Jose State University professor emeritus of political science, considers much of the field to be “staunch Democrats” compared to the moderate Mahan who has had a propensity to “tread a fairly fine line” when it comes to President Donald Trump.

Though Mahan faces challenges with not having wide recognition outside of the Bay Area, Christensen said that the mayor will likely be able to find support from independents if he’s able to raise enough money to reach them — a lane to Sacramento.

While independent or “no party preference” voter registration has declined in recent years, it still sits at about 22%, according to the Public Policy Institution of California.

“He’s more moderate on issues and more outcomes-oriented,” he said. “He’s going to sound like he’s very practical rather than ideological and that he’s going to get stuff done for California and not just fight Trump. I think that will appeal to a significant number of people.”

But the “layer in the uncertainty and unease” that Trump has cast over California has changed voters’ appetite compared to 2018 — when Newsom was first elected — according to Robb Korinke, a Southern California-based political consultant.

While affordability was a winning message for Democrats nationwide in 2025, recent “federal overreach” — particularly around sending federal agents into cities to conduct immigration enforcement — has begun to overshadow kitchen-table issues in polling, Korinke said.

“I don’t think with a straight face you can go to Democratic voters and say I’m worried about your PG&E bill and housing cost and all of these things and not be strong on (Trump) as well,” he said.