Key Takeaways
- ▸ California’s nonpartisan top-two primary system is forcing traders to price who advances, not just who wins, creating more complex and active markets.
- ▸ Polymarket has drawn over $9.1M and Kalshi over $6.5 million in volume on the race, forecasting a Republican advancer but a Democratic general election winner.
- ▸ With no incumbent and polling still unsettled, traders are eyeing real trading opportunities ahead of the June 2 primary.
The 2026 California primary race for governor is wide open and already drawing serious money on prediction markets.
Gov. Gavin Newsom is term-limited and eyeing a 2028 presidential run. The race for the governor seat is drawing a wide range of candidates heading into the June 2 primary. The state’s top-two primary forces a different kind of betting logic, and traders are trying to decide whether the field breaks toward a Democratic advance, a Republican advance, or something stranger.
The primary has drawn more than $9 million in volume on Polymarket, while Kalshi traders are a bit slower to move on the race with just over $300,000 in its primary advancers market.
Why the California governor race matters
California is the biggest prize in the country, but its governor’s race is also structurally unusual because the primary is nonpartisan and only the top two winners advance. That novelty has made California governor markets attractive targets for prediction market traders.
Traders aren’t just pricing a Democrat-versus-Republican general election, they’re also pricing who survives June 2 and who gets boxed out by vote-splitting in the primary.
Newsom being term-limited matters because it removes the incumbent anchor that usually steadies California statewide politics. That has opened the door to a crowded field and a market that looks more fluid than the state’s deep-blue reputation might suggest.
California governor primary polling
Polling has shown a volatile primary field with multiple candidates in the mix and lots of undecideds. Emerson’s polling has swung from a race led by Katie Porter and Steve Hilton to one where Rep. Eric Swalwell has entered and shaken up the Democratic side, while Republicans like Hilton and Chad Bianco remain in the fight.
The latest New York Times polling page frames the field as still unsettled, with no clear frontrunners. In turn, traders are reacting to a race where the top-two primary can produce a final pairing that feels counterintuitive until the votes are actually counted.
What Polymarket is saying
Polymarket’s California governor boards show just how much money is already in the race. The main California Governor Election Winner market has $8.7 million in volume, with Democratic candidate Tom Steyer pacing the field at 38% and Swalwell just behind at 34%.
The companion Who will advance from the California Governor Primary market has more than $455K in volume, with Hilton at 82% and Steyer at 41% in the market’s current pricing. Swalwell is a close third with 36%.
Traders appear as though they are not treating the primary and the general election as the same question. They are pricing Hilton as a strong bet to advance with Republican support. Meanwhile, Steyer and Swalwell remain serious contenders if they advance in the broader winner market because California’s general election environment is still heavily Democratic.
What Kalshi is saying
On Kalshi’s California Governor primary advancers market, Hilton has the highest odds of advancing at 82%. Swalwell follows at 45% implied odds with Steyer close behind at 41%. The market has more than $328K in notional trading volume already.
Kalshi’s CA governor winner market has attracted over $6.2 million in notional trading volume, with Steyer leading at 38% to Swalwell’s 34%, with Hilton trailing at 7%.
Kalshi also has recently released a variety of other related markets, including:
- California Governor primary advancers party: 1 Democrat and 1 Republican leads with 81%
- First place candidate: Hilton 41%, Swalwell 27%
- Second place: Hilton 42%, Swalwell 33%
- Third Place: Steyer 29%, Swalwell 28%
Kalshi is giving traders a way to price the mechanics of the California system, not just the final result. In a top-two state, that matters a lot, because the real action often happens before the general election even exists in a meaningful form.
Prediction market read on California election
California is shaping up as a race where volume is the story as much as the odds. Polymarket traders alone have put millions into the general election market and hundreds of thousands into the advancement market. Kalshi has layered on its own set of primary contracts.
Prediction markets are interested in California’s unusual system that creates more uncertainty than a casual observer would expect. Traders are effectively saying: Yes, Democrats still have the edge. However, the path through the top-two primary is messy enough to open up attractive trading opportunities.
Following the primary, it remains to be seen if the California market maintains its volume pace as the field narrows. If the primary produces a surprising matchup, the odds could swing hard, and fast. If it settles into the expected partisan shape, the market may drift back toward a more familiar blue-state outcome.
Pat Evans
Pat Evans has nearly two decades of experience covering complex industries. Before joining Defi Rate in 2026, he spent more than 15 years writing about sports betting, food and beverage, construction, health care and sports business for national and regional outlets. He previously worked as a reporter and editor for publications including the Grand Rapids Business Journal, Front Office Sports, Legal Sports Report and iGaming Business, where he began in-depth reporting on prediction markets. Pat holds a political science degree from Michigan State University.
