2026 California's 48th Congressional District Election

California's 48th Congressional District is an open U.S. House seat after Republican incumbent Darrell Issa retired rather than seek reelection in a district redrawn by Proposition 50, which shifted the seat roughly 18 points toward Democrats and gave it a slight Democratic voter-registration edge. The June 2 top-two primary advanced Republican San Diego County Supervisor Jim Desmond and Democrat San Diego City Councilmember Marni von Wilpert to the November 3 general election, a race widely seen as one of the few that could decide control of the House.

The first general-election poll (Lake Research Partners, released July 27, 2026) showed von Wilpert leading 48% to 46%, and a September SurveyUSA poll found her ahead 45% to 42% with 13% undecided. Desmond, endorsed by President Donald Trump, Issa, and the California Republican Party, campaigns on border security, affordability, and local government experience; he was added to the NRCC's MAGA Majority program and hosted a late-September fundraiser with House Speaker Mike Johnson.

Von Wilpert, endorsed by EMILYs List, the DCCC's Red to Blue program, Sen. Adam Schiff, and former Vice President Kamala Harris, emphasizes abortion rights, lowering costs, and opposing Trump's agenda. Outside groups are active on both sides, including a pro-Trump super PAC that has spent more than $175,000 attacking von Wilpert.