A campaign to plug California’s leaky health care system by squeezing the state’s richest has a high-profile opponent: Gov. Gavin Newsom. 

Dan Newman, a political adviser opposing the campaign to tax billionaires, said Newsom is against a plan to slap a one-time, 5% tax on roughly 200 Californians worth more than $1 billion to “replace lost federal dollars and protect essential services,” as described by the campaign’s website.

California Governor Gavin Newsom speaks in Houston in Nov. 8, 2025. Getty Images

If enacted, tech titans like Meta CEO Mark Zuckerberg and Nvidia’s Jensen Huang could see colossal tax bills running in the billions. Five percent of Huang’s estimated net worth is equivalent to roughly $8 billion, and Zuck’s tax bill could total more than $12 billion. 

The revenues are intended to fund health care services and the state’s struggling school system, according to supporters. 

Backers of the billionaire tax, who include the SEIU United Healthcare Workers West, Los Angeles nonprofit St. John’s Community Health and former U.S. Secretary of Labor Robert Reich, claim it’s needed in light of federal funding cuts to Medi-Cal and other health care programs. 

California Governor Gavin Newsom speaks in Sacramento in Nov. 4, 2025. Getty Images

The governor’s opposition is a blow to progressives and labor interests backing the tax plan, which could raise some $100 billion over five years, according to supporters. Opponents of the tax say it could drive wealthy residents out of California, ultimately worsening the state’s colossal budget deficit. 

Newsom’s office did not immediately respond to a request for comment. 

Suzanne Jimenez, chief of staff at SEIU-UHW, told The Post she believes Newsom and others with reservations about the tax will ultimately lend their support.

“California’s frontline healthcare workers welcome and look forward to a good faith dialogue with our governor around these critical issues as the November 2026 vote draws closer,” Jimenez said. 

California Gov. Gavin Newsom speaks in Sacramento on Oct. 28, 2025. REUTERS

Last year, facing a deficit in excess of $44 billion, Newsom publicly opposed general tax increases and noted the state’s already sky-high levies on corporations and wealthy individuals. In recent years, California’s skyrocketing cost of living has led residents to flee the state in droves alongside corporations like Tesla that cited high taxes and onerous regulations.

Newsom is widely expected to enter the 2028 race for president, telling CBS News in October that he’ll make a decision after the 2026 midterm elections. And the two-term governor is likely to pass the hat among power players in Hollywood and SIlicon Valley if and when he launches his bid for the White House. 

Newsom has received campaign cash from billionaires such as Netflix co-founder Reed Hastings, philanthropist Laurene Powell Jobs, and former Google CEO Eric Schmidt, among others. And the former San Francisco mayor famously got his start in politics with the support of Gordon Getty, heir to the Getty oil fortune and a family friend. 

California Gov. Gavin Newsom speaks at a rally in Houston on Nov. 8, 2025. AP

Tinseltown bigwigs known to fund the ambitions of high-profile Democrats have applauded Newsom’s anticipated presidential campaign. 

“He’s a fighter, that’s what we need!” a Hollywood producer described as a “reliable Dem ATM” told Deadline. 

“Big checks are being written,” former Obama US Ambassador to Spain and HBO executive James Costos told the website. 

Major donors are keen to ride the bandwagon if Newsom’s campaign for president takes off, another unnamed donor told Deadline.

Supporters of the billionaire tax, dubbed the “2026 Billionaire Tax Act,” have filed paperwork with the Attorney General’s office and must gather 874,641 signatures to place it on the November 2026 ballot.