California's 31st congressional district (CA-31) is a competitive U.S. House seat located in San Bernardino County, encompassing parts of the city of San Bernardino, Colton, Rialto, and unincorporated areas like Muscoy and Bloomington. The district was created after the 2020 redistricting cycle and first contested in 2022. It is considered a toss-up or lean Democratic district by most nonpartisan analysts, with a Cook Partisan Voting Index (PVI) of D+7 as of 2024. The current representative is Democrat Gil Cisneros, who was first elected in 2024 after defeating Republican John Sweeney. The 2026 election for the term beginning in 2027 will determine who represents this district in the 119th Congress. The race is expected to be one of the most competitive in California, with national implications for control of the House. The district's demographics are diverse: approximately 60% Hispanic, 20% White, 10% Asian, and 8% Black. The median household income is around $65,000, and about 16% of residents live below the poverty line. The district includes a mix of suburban and urban areas, with a significant working-class population. The 2026 election will be held on November 3, 2026, with primary elections likely in June 2026. The outcome could hinge on turnout among Latino voters, the strength of the local Democratic Party organization, and national trends such as inflation, immigration policy, and the approval rating of the president. The district has a history of close elections: in 2022, Cisneros won by 6.4 percentage points, and in 2024, he won by 5.2 points. Both margins were narrower than the district's partisan lean, reflecting its swing nature. The race is being closely watched by both national parties, with the Democratic Congressional Campaign Committee (DCCC) and the National Republican Congressional Committee (NRCC) likely to invest heavily in advertising and ground operations. The outcome will affect the balance of power in the House, where the 2026 elections will determine which party controls the chamber for the final two years of the presidential term. The district is also a bellwether for Latino voting patterns in California, which have shifted toward Republicans in some areas in recent cycles. The 2026 race will test whether Democrats can hold onto working-class Latino voters or whether Republicans can make further inroads.

Historical Context

California's 31st congressional district has existed in various forms since the 1970s. The current iteration was drawn after the 2020 census, when California lost a congressional seat due to population decline. The district was designed to be a Latino-majority seat, with a 60% Hispanic population. It replaced the old CA-31, which was held by Democrat Pete Aguilar until 2022, when he moved to the new CA-33. The district's boundaries were drawn by the California Citizens Redistricting Commission, an independent body, to comply with the Voting Rights Act by ensuring Latino voters had a fair chance to elect their preferred candidates. The district has a history of close elections. In 2022, the first election under the new map, Democrat Gil Cisneros won by 6.4 points over Republican John Sweeney. In 2024, Cisneros won by 5.2 points. Both margins were smaller than the district's D+7 PVI, suggesting that the district is more competitive than its partisan lean indicates. The 2024 election saw a significant shift in Latino voting patterns nationwide, with some districts in California seeing a 10-15 point swing toward Republicans among Hispanic voters. In CA-31, this trend was visible in precincts with high concentrations of working-class Latino voters. The district also has a history of low voter turnout, with only 55% of eligible voters casting ballots in 2024. This is below the state average of 62%. The district's electorate is younger than the national average, with a median age of 32. This demographic is less likely to vote in midterm elections, which could affect the 2026 race. The 2026 election will be the third contest in this district, and patterns from the first two elections suggest that the race will be decided by a margin of 3-7 points. The district has not elected a Republican since 1992, when it was a different geographic area. The last Republican to represent any part of the current district was Jerry Lewis, who served from 1978 to 2012 in the old CA-40 and CA-41.