Support for California's Proposition 40 has fallen below a majority, according to a Public Policy Institute of California (PPIC) survey released in October.

The poll found 46% of likely voters would vote yes on the measure, down from 52% in September. Fifty-two percent said they would vote no. The survey was conducted Oct. 16–22.

Prop. 40 would impose a one-time 5% tax on certain taxpayers with assets exceeding $1 billion. Ninety percent of the revenue would go toward health care, with the remaining 10% directed to education and food assistance, according to LA Magazine.

The measure drew sharp partisan divides. More than 60% of Democratic voters support the tax, compared with about 20% of Republicans and roughly 40% of independents, according to the PPIC survey. Younger voters ages 18 to 34 and those earning less than $40,000 annually were more likely to back it. Likely voters in Los Angeles were among the most supportive, at 53%.

$317 million opposition campaign

Building a Better California, a nonprofit political committee, leads the opposition. Campaign finance records show the group raised more than $317 million in dated receipts during the 2025–2026 cycle. LA Magazine reported the group has received more than $333 million from donors overall.

Among the major contributors: former Google CEO Eric Schmidt and venture capitalist John Doerr each gave more than $40 million, according to LA Magazine. Google co-founder Sergey Brin, who lives in Nevada, contributed more than $100 million.

The group argues Prop. 40 would "damage California's economy and cost the state budget billions in lost revenue – all without doing anything to lower healthcare costs," according to LA Magazine.

Sanders rallied in LA; Becerra opposes the measure

Sen. Bernie Sanders held a "YES ON PROP 40" rally in downtown Los Angeles earlier in October, urging Angelenos to vote yes. Sanders argued the tax would help prevent more than 3 million working-class Californians from losing health coverage and help keep hospitals and emergency rooms open, LA Magazine reported.

"The whole country is watching you," Sanders told attendees. "Because if you stand up to this wealth and power and arrogance, trust me — the rest of the country will not be far behind."

Gubernatorial candidate Xavier Becerra, who leads Republican Steve Hilton 61% to 37% in the PPIC poll, has spoken out against Prop. 40. In an interview with KCRA's California Politics 360 published Oct. 29, Becerra said there are "real complications" when individuals are taxed on their assets.

"Having done tax policy for over 20 years in Congress, you want to make sure it's something that's fair, predictable, and stable," Becerra said. He said his own plan to tax the wealthy would focus on income taxes instead.

Two counter-propositions on the same ballot

Propositions 41 and 42, backed by Prop. 40 opponents, also appear on the Nov. 3 ballot. Prop. 41 would require audits of programs funded by new special taxes and restrict the state from exempting new taxes from its spending limit. The PPIC poll found 48% of voters support it. Prop. 42 would prohibit California from imposing certain new taxes on personal and financial assets. It drew 51% support.

Both measures conflict with Prop. 40. If voters approve all three, the outcomes could undercut one another.

All Los Angeles County Vote Centers are open through Election Day on Nov. 3. Voters can cast ballots by mail, at an official drop box or in person at any Vote Center.