California House Races 2026: The Competitive Seats

Our Take

The draft map tells you where to look, not what will happen. Prop 50 reshaped five Republican seats so much that 2024 results are a weak guide there, while the two tightest Democratic holds, CA-13 and CA-45, are where old margins still matter most. District contracts are also far thinner than the House control contract, so read the order book before you trade a price.

What Prop 50 changed

California voters approved Proposition 50 on November 4, 2025, replacing the independent commission's congressional map with a new one for 2026 through 2030. The new lines targeted the five seats Republicans held after the 2024 election, in the far north, the Sacramento suburbs, the Central Valley, the Inland Empire and North San Diego County.

Several incumbents moved or left as a result:

• •CA-1: Rep. Doug LaMalfa (R) died in January 2026. Republican James Gallagher won the special election to finish his term and is running in the redrawn seat.
• •CA-3 → CA-6: Rep. Kevin Kiley left the Republican Party, is running with no party preference, and moved to the new Sacramento-area CA-6.
• •CA-41 to CA-40: Rep. Ken Calvert was drawn out of his seat and is running in CA-40 against fellow Republican Rep. Young Kim.
• •CA-48: Rep. Darrell Issa (R) retired, leaving an open seat.

The Prop 50 seats

• •CA-1 (far north): Gallagher, a former Assembly Republican leader, faces Democratic state Sen. Mike McGuire. The redrawn district adds Democratic territory the old North State seat never had.
• •CA-6 (Sacramento suburbs): Kiley, now running outside either party, faces Democrat Richard Pan, a former state senator.
• •CA-22 (Central Valley): Rep. David Valadao (R), who has held this seat through several close cycles, faces Democrat Randy Villegas. The new lines add part of Fresno and eastern Bakersfield.
• •CA-48 (San Diego and Riverside counties): Republican Jim Desmond faces Democrat Marni von Wilpert for Issa's open seat, which CalMatters describes as shifting from "deep red to slightly blue" under Prop 50.
• •CA-41 (Los Angeles and Orange counties): Calvert's old seat became a Democratic-leaning district. Rep. Linda Sánchez (D) faces Republican Mitch Clemmons.

CA-40 is different. With two Republicans in the final, the party of the winner is already settled, so any contract here is about which incumbent survives, not about House control.

The Democratic seats Republicans are targeting

• •CA-13 (San Joaquin Valley): Rep. Adam Gray (D) flipped this seat by 187 votes in 2024, and the Associated Press took nearly a month to call it. The new boundaries include southern Stockton and moved the seat slightly left. He faces Republican Kevin Lincoln, a former Stockton mayor.
• •CA-45 (Orange County): Rep. Derek Tran (D) won by 653 votes in 2024, 50.1% to 49.9%. He faces Republican Chuong Vo.

These were the two closest California House races of 2024. Also worth watching on some lists: CA-27 in north Los Angeles County, where Rep. George Whitesides (D) faces Republican Jason Gibbs.

How to read a redistricted-seat contract

• •Discount the 2024 result. In the Prop 50 seats, a large share of voters are new to the district, so last cycle's margin says less than usual.
• •Check liquidity. District contracts trade far less than the House control contract. A wide gap between the best bid and ask can make a price look more certain than it is. Our guide on how to read an order book walks through it.
• •Read the settlement rules. California counts late mail ballots for weeks, and the Secretary of State certifies results on December 11, 2026. Each platform sets its own settlement source and timing.
• •Mind the member-vs.-member race. In CA-40, the question is which Republican wins, not which party.

Is trading House race contracts legal in California?

Yes. Kalshi and Polymarket US operate as CFTC-regulated exchanges, and California has not taken statewide action to block them as of September 26, 2026. There is nothing district-specific: access is the same in most of California. For the full picture, see Is it legal in California?.

Recent rulings mostly concern sports contracts:

• •Ninth Circuit, KalshiEX LLC v. Assad (August 28, 2026): The federal appeals court that covers California ruled that Nevada can likely enforce its gaming laws against Kalshi's sports contracts. It sent the question of election contracts back to the lower court rather than deciding it. Kalshi asked for a rehearing on September 9, 2026. The Third Circuit reached the opposite view earlier this year (see our Third Circuit ruling coverage), so Supreme Court review is possible.
• •CFTC proposal (June 10, 2026): The CFTC's proposed prediction-market rules treat election outcomes as outside the "gaming" category. It is a proposal, not a final rule.

We'll update this page as the courts and the CFTC act.