Corporations, labor unions, tech titans, Native American tribes and other special interests have donated a record-breaking $79.6 million to independent committees focused on swinging the California governor’s race ahead of the June 2 primary.
Many of the biggest supporters of these committees will have significant business interests in the state’s next governor and state agencies, hoping to either strengthen the candidate in line with their political preferences or weaken those who oppose them.
“This is the first time I’ve seen IE (or independent expenditure) have this kind of impact on a governor’s race,” said veteran GOP strategist Martin Wilson, who has worked on every California gubernatorial contest since 1978 and worked on an outside effort to support San Jose Mayor Matt Mahan’s 2026 bid for governor. “This is completely unprecedented.”
Election laws prevent independent expenditure committees from communicating or coordinating with campaigns, allowing candidates to emphasize that they have no control over the money poured into these outside groups. The wall between the two has long been considered performative and penetrable.
The largest amount of outside spending has been directed at attacking billionaire hedge fund founder-turned-environmental crusader Tom Steyer, the leading Democrat in the race.
As of Monday, about $32.3 million had been donated to oppose his candidacy, according to the California Target Book, a non-partisan political almanac that tracks independent expenditure committees. Major donors include utility giant PG&E, the California Chamber of Commerce and a political action committee sponsored by the California Association. Realtors’ independent expenditure committee, which jointly consults with lawmakers and regulators in the state capital on utility, business, property tax and building issues.
According to the California Secretary of State’s office, independent spending supporting Steyer’s bid for governor is minimal, while Steyer has donated a record-breaking $212 million to his own campaign as of Monday. Nevertheless, more than $1.4 million of outside money has been spent in support of his bid, primarily by the California Nurses Association, which shares his goal of creating single-payer healthcare.
Expense committees involving Uber, the California Medical Association, kidney dialysis company DaVita and the California Dental Association. Contributed nearly $7.3 million to independent efforts in support of former Rep. Eric Swalwell (D-Dublin) before he dropped out of the gubernatorial race in April due to sexual harassment and misconduct allegations.
Recent opinion polls show many of those donors rallied behind former Biden Cabinet member Xavier Becerra, who struggled to connect with California voters before becoming the front-runner. More than $13 million has been contributed to outside groups supporting the former U.S. Secretary of Health and Human Services.
Outside money has created conflict in the race. Steyer points to corporations supporting Becerra, such as a $500,000 Chevron donation to a group supporting him, which was reported to state elections officials on Thursday.
Steyer spokesman Anthony York said, “The Becerra campaign was running out of gas until the latest half-million-dollar infusion from Chevron.”
The message echoes a Steyer theme on the campaign trail – that candidates should be evaluated based on who is supporting them and who is opposing them.
Becerra accused Steyer of misleading voters because $500,000 from Chevron went to an independent expenditure committee supporting him over which he has no control. However, Becerra received a $39,200 contribution directly from the oil company to his campaign committee in June 2025.
“Their statement that I took ($500,000) … that’s a blatant lie,” he said in a television interview this weekend. “It saddens me to see candidates running for office believe they have to lie to curry favor with voters. If you do this as a candidate, what will you do when you’re in office?”
Steyer’s campaign, which had used the Memorial Day weekend to attack Becerra with billboards highlighting high gas prices in Los Angeles and Fresno, said it was disingenuous for Becerra to show ignorance about how the political system works.
“Chevron is charging Californians record gas prices on one hand and spending $500,000 to elect Xavier Becerra on the other,” said Steyer spokesman Danny Wang. “Now Becerra is playing semantic gymnastics and trying to pretend that voters are too stupid to understand how dark money works in politics. Californians aren’t buying it.”
Becerra’s campaign argued that such comments were the height of hypocrisy coming from a billionaire whose campaign was funded by his profits from a hedge fund that had made investments that many voters opposed. Becerra said he consistently took aim at oil companies while serving as California attorney general.
Becerra spokesman Jonathan Underland said, “Tom Steyer made billions of dollars from fossil fuels and private prisons, then decided he was qualified to run California.” “He’s now attacking the only candidate in this race who actually held Big Oil’s feet to the fire and defeated (President) Trump 100 times as a (state attorney general). The irony would be funny if Tom’s checkbook wasn’t so fat.”
According to Target Book, Mahan, a moderate Democrat, has benefited from $21.7 million spent by outside groups supporting him, while $570,000 has been spent by independent committees opposing him. Donors supporting his bid include many from Silicon Valley, including venture capitalists Michael Moritz and L. John Doerr, Stripe chief executive Patrick Collinson and Sun Microsystems co-founder Vinod Khosla. Other notable donors include billionaire real estate developer Rick Caruso, who ran unsuccessfully for mayor of Los Angeles in 2022, as well as Griff Hersh V, son of billionaire Meg Whitman, an unsuccessful 2010 GOP gubernatorial candidate turned Democrat who once led eBay.
Despite that generous support, Mahan is stuck in single digits in the surveys. On Wednesday, billionaire Netflix co-founder Reed Hastings received a refund of $1 million he donated to one of the independent expenditure committees supporting Mahan’s bid.
Hastings said he did not request a return of the money.
“I’m voting for Matt Mahan. I didn’t ask for a refund and they shouldn’t have done that,” he posted on Twitter on Saturday. “Go Matt.”
Matt Rodriguez, a spokesman for the Back to Basics Committee, which supports Mahan, said he believes Mahan’s standing in the race is a reflection of several factors – a fierce competition as well as Mahan’s entry into it in January and the fact that he was not well known throughout the state.
“He arrived a little late and it was a big climb … with apathetic voters,” Rodriguez said. “Politics is all about money and time – both the amount of time and being present at the right time.”
The Democratic strategist said Mahan’s priorities, such as improving housing and homelessness, which he oversaw in San Jose, had an impact on the campaign.
“Democrats have to perform, and if we’re going to perform, we have to get results,” he said.
The only other candidate who saw seven figures in independent campaign spending was Republican Steve Hilton, a former Fox News commentator who has been endorsed by Trump and is the leading GOP candidate in the race. More than $1.8 million has been spent opposing Hilton and $13,750 has been spent in support of him.
SEIU California donated $250,000 to opposing gubernatorial candidates. Oscar Lopez, the union’s political director, said it has opposed Hilton, Mahan and Republican Riverside County Sheriff Chad Bianco.
“Each of these candidates represents a serious threat to the wages, rights and dignity of working people of California,” Lopez said.
Hilton said the spending against him represented Democratic recognition of him as a threat.
“They know they’re vulnerable. The Democratic machine understands they have a weak candidate and he has a very bad record,” he said in an interview. “They see me as an outsider and a change agent. The only logic they have — if you can call it logic — is to repeat the words Trump and MAGA endlessly.”
Outside spending has increased sharply since voters approved a 2000 California ballot measure that limited how much donors could contribute directly to candidates. For the current election, it is $78,400 for the primary and general election in the governor’s race.
But donors can contribute unlimited amounts to outside groups, formally called independent expenditure committees. Although such donations were already legal in California, they increased significantly in the state and across the country following the U.S. Supreme Court’s 2010 Citizens United decision, which held that limits on independent political spending by corporations, unions, and other entities violate First Amendment free speech protections.
“There has been a steady increase in the amount of money going to outside groups,” said Rick Hassan, a professor of law and political science at UCLA.
In California, independent expenditure groups set a record in 2010 when they spent nearly $25 million in support of then gubernatorial candidate Jerry Brown. Largely funded by union money, it was spent the summer after the primaries and was seen as crucial to thwarting the campaign of self-financed Republican billionaire Meg Whitman. Brown ultimately won the race by 13 percentage points.
In the 2018 gubernatorial primary, records were once again broken by outside spending of more than $26 million, with former Los Angeles Mayor Antonio Villaraigosa the largest beneficiary. Charter school supporters spent approximately $16 million on unsuccessful efforts to promote their campaign.
In addition to having enormous financial leverage over campaign committees, outside groups often have the ability to mount highly provocative adverse attacks without the candidate being blamed for the controversial message.
“IEs are free to go as negative as they want without the negativity hurting the candidate,” said Thad Kousser, a political science professor at UC San Diego.
While communications between candidate campaigns and independent committees are prohibited, these rules are generally circumvented using legal but obvious methods. One called “red boxing,” which Becerra employed earlier this year, literally puts messages inside red-lined boxes on candidate websites that their campaign strategists want to see exposed to outside groups.
“There are technical rules that prevent certain types of communication, but it’s quite easy to communicate publicly and be on the same page over messaging,” Hasen said.
Major donors to the 2026 campaign include the California Chamber of Commerce, PG&E, California Assn. Realtors, Laborers Pacific Southwest Regional Organizing Coalition PAC, Pechanga Band of Indians, California Nurses Association, and corporations and leaders or founders of companies like Meta, Google, and Uber.
Californians for the People, an outside committee that has spent nearly $32.3 million opposing Steyer, is the best-funded independent expenditure committee this year. Among its largest donors is JOBSPAC, a group sponsored by the California Chamber of Commerce, which has donated approximately $11.8 million to the effort.
Chamber spokesman John Myers said, “CalChamber is participating in an independent expenditure campaign because voters deserve to know more about Mr. Steyer.” “His policy promises will cost billions of dollars, drive investment out of California and worsen the state’s affordability crisis.”
The Pechanga Band of Indians has spent $1.5 million on pro-Becerra efforts.
“Secretary Becerra has stood with Indian Country for decades and understands tribal sovereignty,” said Pechanga Chairman Mark Macaro. “When tribal health services were on the line, he was there. That’s experience that comes from a lifetime of public service, not from a chequebook.”
