California's 12th congressional district

California's 12th congressional district is a congressional district in northern California. Barbara Lee, a Democrat, has represented the district since January 2023.

Currently, the 12th district is located in Alameda County and includes the cities of Oakland, Berkeley, Emeryville, Alameda, Albany, Piedmont, and most of San Leandro. With a Cook Partisan Voter Index rating of D+40, the 12th district is the most Democratic district in both California and the United States, giving nearly 90% of its vote to Democrats in both the 2016 and 2020 presidential elections.

Before redistricting in 2023, the 12th district was within San Francisco, encompassing most of the city. The remainder of the city was included in the 14th district.

History
When the district was created after the 1930 census, it was located in Los Angeles County. As California's population grew, however, the district generally was moved northward, eventually to the San Francisco peninsula.

Richard Nixon, who would subsequently serve as the 37th president of the United States, represented this district from 1947 to 1951. Nancy Pelosi, the former speaker of the House, represented the district from 2013 to 2023. She had previously served California's 5th congressional district from 1987 to 1993 and California's 8th congressional district from 1993 to 2013 and currently represents California's 11th congressional district.

Composition
Due to the 2020 redistricting, California's 12th district has effectively been shifted to the former geography of the 13th district. It encompasses the coastal section of Alameda, and is anchored by Oakland. This district borders the 13th district, and Alameda County is partitioned between them by Grant Ave, Union Pacific, Lewelling Blvd, Wicks Blvd, Manor Blvd, Juniper St, Dayton Ave, Padre Ave, Fargo Ave, Edgemoor St, Trojan Ave, Beatty St, Fleming St, Highway 880, Floresta Blvd, Halcyon Dr, Hesperian Blvd, Thornally Dr, Highway 185, 150th Ave, Highway 580, Benedict Dr, San Leandro Creek, and Lake Chabot Regional Park. Alongside Oakland, the 12th district takes in the cities of Alameda, Albany, Berkeley, Emeryville, Piedmont, and San Leandro.

Cities

 * Oakland – 440,646
 * Berkeley – 124,321
 * San Leandro – 91,008
 * Alameda – 77,624
 * Albany – 20,271
 * Emeryville – 12,905
 * Piedmont – 11,270