Billionaire investor Tom Steyer has announced he will not launch a bid for the White House in the 2028 presidential election.
Steyer is among the frontrunners in the competitive California gubernatorial election.
With Eric Swalwell’s exit from the race, Steyer’s chances of advancing to the general election have significantly increased.
Swalwell had led prediction markets for months before allegations upended his campaign, creating a vacuum in a race already defined by fragmentation. His sudden exit has accelerated momentum around Steyer, reshaping expectations less than seven months before Election Day.
Prediction markets now show Steyer with a commanding lead over his remaining rivals, according to data from Kalshi and Polymarket, two platforms where users trade on real-world political outcomes.
On Polymarket, Steyer was priced at roughly 59 percent at the time of writing, up a significant 52.7 points from just 6.3 percent on March 22, compared with Matt Mahan at about 14 percent and Katie Porter near 14 percent. Trading volume on the market has surpassed $9 million, reflecting strong interest following Swalwell’s exit.
Kalshi shows a nearly identical picture. Traders there give Steyer a roughly 55 percent chance of winning, up 40.6 points from just 14.4 percent on April 4, while both Matt Mahan and Katie Porter sit at 15 percent. Combined trading volume across governor-related Kalshi contracts now exceeds $22 million.
In a new poll conducted after Swalwell’s exit, Steyer was in a dead-heat for second place in California’s jungle primary.
He dropped out of the 2020 presidential race after losing three Democratic primary contests and spent nearly $250 million of his personal funds on that campaign.
Steyer has since donated $112 million to his 2026 gubernatorial campaign, dwarfing the hauls of his opponents. Forbes has estimated Steyer’s net worth at $2 billion.
Running on a platform that includes universal healthcare and free college, Steyer has aligned himself with progressive figures like Sen. Bernie Sanders, who has called him a “friend,” though Sanders has also said he is not a “fan of billionaires getting involved” in politics.
Steyer left the hedge fund he founded in 2012 to pursue his climate and clean energy advocacy work, which included creating his climate advocacy group NextGen America.
His money and campaigning have been behind three successful ballot measures and helped prevent another, including donating $12 million to California Proposition 50, the “Election Rigging Response Act” in 2025. The measure was passed, allowing for California to redraw its congressional districts to incorporate larger shares of urban and suburban voters, which Republicans unsuccessfully challenged in court.
In 2010, he joined a campaign and donated $5 million to defeat Proposition 23, backed by billionaire brothers Charles and David Koch. The measure sought to overturn California’s Global Warming Solutions Act of 2006. He also led measures that closed tax loopholes allowing corporations to avoid paying taxes in California and raised taxes on tobacco to supplement healthcare programs.