Incumbent Mike Thompson seeks a fifteenth term in California’s 4th Congressional District under the state’s top-two primary system, where the two highest vote-getters advance to November regardless of party. Redistricting added more rural and conservative territory, yet Thompson maintains strong name recognition and fundraising. Democratic challenger Eric Jones, a former venture capitalist, has emerged as the most viable opponent with substantial cash reserves and an endorsement from Senator Bernie Sanders, positioning both candidates to dominate the June 2, 2026 ballot. Six Republican entrants and one independent are expected to split opposition votes, reducing any single GOP candidate’s chance of advancing. Trader consensus reflected in current pricing centers on Thompson and Jones clearing the field, with limited recent polling or last-minute shifts altering that outlook ahead of election day.