California's 1st congressional district


California's 1st congressional district is a U.S. congressional district in California. The district is currently vacant following the death of Doug LaMalfa, a Republican, who had represented the district since January 2013. There will be a special election to fill the seat on August 4th, 2026, with a primary election on June 2nd. Currently, the district encompasses many northeastern parts of the state. Since the 2022 election, it includes the counties of Butte, Colusa, Glenn, Lassen, Modoc, Shasta, Siskiyou, Sutter, and Tehama, and most of Yuba County. The largest cities in the district are Chico, Redding, and Yuba City.
Prior to redistricting in 2021, it included the counties of Butte, Lassen, Modoc, Plumas, Shasta, Sierra, Siskiyou, and Tehama, most of Nevada County, part of Glenn County, and part of Placer County. In the 2021 redistricting, it added the Yuba–Sutter area and removed most of its share of the Sierra Nevada.

Competitiveness

Prior to 2013, the GOP last held the seat in 1998 when U.S. Representative Frank Riggs decided to run for the U.S. Senate. Riggs was replaced by long-time Democratic Assemblyman and State Senator Mike Thompson. Redistricting in 2001 added Democratic-leaning areas of Yolo County.
John Kerry won the district in 2004 presidential election with 59.7% of the vote. Barack Obama carried the district in 2008 presidential election with 65.60% of the vote. The redistricting after the 2010 census made the district much more Republican-leaning; Mitt Romney and Donald Trump won the district by double digits in 2012, 2016, 2020, and 2024 respectively.

Recent election results from statewide races

2023–2027 boundaries

Composition

Under the 2020 redistricting, California's 1st district is located in northeastern California, encompassing Butte, Colusa, Glenn, Lassen, Modoc, Shasta, Siskiyou, Sutter, and Tehama Counties, as well as part Yuba County. The area in Yuba County includes the cities of Marysville and Wheatland; and the census-designated places of Beale AFB, Linda, Olivehurst, and Plumas Lake.
Yuba County is split between this district and the 3rd district. They are partitioned by State Highway 70, Ellis Rd, and Union Pacific.

Cities and CDPs with 10,000 or more people

Election results

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