California's 10th congressional district is a

congressional district Congressional districts, also known as electoral districts and legislative districts, electorates, or wards in other nations, are divisions of a larger administrative region that represent the population of a region in the larger congressional bod ...

in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sove ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

. Currently, the 10th district encompasses parts of the eastern

San Francisco Bay Area The San Francisco Bay Area, often referred to as simply the Bay Area, is a populous region surrounding the San Francisco, San Pablo, and Suisun Bay estuaries in Northern California. The Bay Area is defined by the Association of Bay Area Go ...

. It is currently represented by

Democrat Democrat, Democrats, or Democratic may refer to: Politics *A proponent of democracy, or democratic government; a form of government involving rule by the people. *A member of a Democratic Party: **Democratic Party (United States) (D) **Democratic ...

Mark DeSaulnier Mark James DeSaulnier ( ; born March 31, 1952) is an American politician who has served as the U.S. representative for California's 11th congressional district since 2015. The district includes most of Contra Costa County, a suburban county ...

. The district previously included all of Stanislaus County and part of

San Joaquin County San Joaquin County (; Spanish: ''San Joaquín'', meaning " St. Joachim"), officially the County of San Joaquin, is a county in the U.S. state of California. As of the 2020 census, the population was 779,233. The county seat is Stockton. San ...

. It was centered on

Modesto Modesto () is the county seat and largest city of Stanislaus County, California, United States. With a population of 218,464 at the 2020 census, it is the 19th largest city in the state of California and forms part of the Sacramento-Stockton ...

. Cities in the district included Oakdale, Manteca, Modesto, Tracy, and

Turlock Turlock is a city in Stanislaus County, California, United States. Its estimated 2019 population of 73,631 made it the second-largest city in Stanislaus County after Modesto. History Founded on December 22, 1871, by prominent grain farmer Jo ...

. Redistricting before the 2022 elections moved the district to the

. It includes the cities of

Concord Concord may refer to: Meaning "agreement" * Pact or treaty, frequently between nations (indicating a condition of harmony) * Harmony, in music * Agreement (linguistics), a change in the form of a word depending on grammatical features of other ...

Walnut Creek A walnut is the edible seed of a drupe of any tree of the genus ''Juglans'' (family Juglandaceae), particularly the Persian or English walnut, ''Juglans regia''. Although culinarily considered a "nut" and used as such, it is not a true bo ...

, Danville, San Ramon, Brentwood, and southern

Antioch Antioch on the Orontes (; grc-gre, Ἀντιόχεια ἡ ἐπὶ Ὀρόντου, ''Antiókheia hē epì Oróntou'', Learned ; also Syrian Antioch) grc-koi, Ἀντιόχεια ἡ ἐπὶ Ὀρόντου; or Ἀντιόχεια ἡ ἐπ� ...

in Contra Costa County, and eastern

Dublin Dublin (; , or ) is the capital and largest city of Ireland. On a bay at the mouth of the River Liffey, it is in the province of Leinster, bordered on the south by the Dublin Mountains, a part of the Wicklow Mountains range. At the 2016 c ...

Alameda County Alameda County ( ) is a county located in the U.S. state of California. As of the 2020 census, the population was 1,682,353, making it the 7th-most populous county in the state and 21st most populous nationally. The county seat is Oakland. Alam ...

. The redistricting transformed the 10th from a competitive district to a heavily Democratic one.

History

Until 2012

Prior to redistricting by the California Citizens Redistricting Commission going into effect in 2012, the 10th district stretched from Livermore to Dixon and the outskirts of

Vacaville Vacaville is a city located in Solano County in Northern California. Sitting approximately from Sacramento and from San Francisco, it is within the Sacramento Valley. As of the 2020 census, Vacaville had a population of 102,386, making it ...

. It consisted of portions of

Alameda An alameda is a Avenue (landscape), street or path lined with trees () and may refer to: Places Canada *Alameda, Saskatchewan, town in Saskatchewan **Grant Devine Dam, formerly ''Alameda Dam'', a dam and reservoir in southern Saskatchewan Chile ...

, Contra Costa,

Sacramento ) , image_map = Sacramento County California Incorporated and Unincorporated areas Sacramento Highlighted.svg , mapsize = 250x200px , map_caption = Location within Sacramento ...

, and Solano Counties. Ca10_109

Following redistricting in 1992, the 10th district was based in the

East Bay The East Bay is the eastern region of the San Francisco Bay Area and includes cities along the eastern shores of the San Francisco Bay and San Pablo Bay. The region has grown to include inland communities in Alameda and Contra Costa counties ...

, and included parts of

and Contra Costa counties. It received national attention in 1996 when

Ellen Tauscher Ellen O'Kane Tauscher (November 15, 1951 – April 29, 2019) was an American businesswoman, diplomat, and Democratic Party politician who was the U.S. representative for California's 10th congressional district from 1997 to 2009. From 2009 to 20 ...

defeated incumbent

Republican Republican can refer to: Political ideology * An advocate of a republic, a type of government that is not a monarchy or dictatorship, and is usually associated with the rule of law. ** Republicanism, the ideology in support of republics or agains ...

Bill Baker in what was considered an upset. In the 2002 redistricting of California, all seats were made safe for the parties of incumbent officeholders. The district boundaries were extended to include parts of

Solano County Solano County () is a county located in the U.S. state of California. As of the 2020 census, the population was 453,491. The county seat is Fairfield. Solano County comprises the Vallejo–Fairfield, CA Metropolitan Statistical Area, which i ...

, southwestern

Sacramento County Sacramento County () is a county located in the U.S. state of California. As of the 2020 census, the population was 1,585,055. Its county seat is Sacramento, which has been the state capital of California since 1854. Sacramento County is the ...

, eastern Contra Costa County and El Cerrito in western Contra Costa County. Although much of the suburban

Tri-Valley The Tri-Valley area is grouping of three valleys in the East Bay region of California's Bay Area. The three valleys are Amador Valley, San Ramon Valley, and Livermore Valley. The Tri-Valley encompasses the cities of Dublin, Livermore, Pleasa ...

region was shifted to the 11th congressional district, the city of Livermore remained in the 10th at Tauscher's request (as a member of the

U.S. House Committee on Energy and Commerce The Committee on Energy and Commerce is one of the oldest standing committees of the United States House of Representatives. Established in 1795, it has operated continuously—with various name changes and jurisdictional changes—for more than ...

, she had some oversight responsibilities over the U.S. Department of Energy, and hence indirectly of Lawrence Livermore National Laboratory). On June 26, 2009, Tauscher resigned her seat to be sworn in as Undersecretary of State for Arms Control and International Security. In the ensuing

special election A by-election, also known as a special election in the United States and the Philippines, a bye-election in Ireland, a bypoll in India, or a Zimni election (Urdu: ضمنی انتخاب, supplementary election) in Pakistan, is an election used to f ...

held on November 3, 2009, former Democratic Lieutenant Governor

John Garamendi John Raymond Garamendi (; born January 24, 1945) is an American businessman, politician, and member of the Democratic Party who has represented areas of Northern California between San Francisco and Sacramento, including the cities of Fairfiel ...

won the seat over

David Harmer 53.0% to 42.7%. Immediately following redistricting, Garamendi successfully ran for re-election in

California's 3rd congressional district California's 3rd congressional district is a U.S. congressional district in California. John Garamendi, a Democrat, has represented the district since January 2013. Effective January 2023, California's 3rd congressional district will include ...

, which shares many municipalities with the 2002 version of the 10th district (e.g.

and Fairfield), but lies significantly northwest of the current 10th district.

2012 – 2022

The 10th congressional district starting with the election of 2012 and lasting through the election of 2020 included all of Stanislaus County (including

Ceres Ceres most commonly refers to: * Ceres (dwarf planet), the largest asteroid * Ceres (mythology), the Roman goddess of agriculture Ceres may also refer to: Places Brazil * Ceres, Goiás, Brazil * Ceres Microregion, in north-central Goiás ...

, Oakdale,

, Riverbank, and

) and the southern portion of

(including Tracy and Manteca). This went into effect in 2012, as the result of redistricting by the California Citizens Redistricting Commission. This version of the 10th included much of the core of the old 18th district (

, and the southwestern half of Stanislaus County), though the 18th also included a substantial portion of Stockton. It also shares much of the northwestern portion of the old 19th district (

, Riverbank, Oakdale, and the rest of northeastern Stanislaus County). Republican

Jeff Denham Jeffrey John Denham (born July 29, 1967) is an American politician, United States Air Force veteran, and businessman. A member of the Republican Party, he served as the U.S. representative for from 2013 to 2019. Denham first won election to th ...

transferred from the prior 19th district to the newer 10th. He held it for three terms until being defeated in 2018 by Democrat Josh Harder, who won reelection in 2020.

After 2022

The 10th district was redrawn in time for the 2022 election, being divided up between

California's 5th congressional district California's 5th congressional district is a U.S. congressional district in California. The district is located in the northern San Joaquin Valley and central Sierra Nevada. The district includes all of Amador, Calaveras, Tuolumne and Ma ...

(which now includes eastern portions of

and eastern portions of

), California's 9th congressional district (which is centered on Stockton, California and includes Tracy), and

California's 13th congressional district California's 13th congressional district is a congressional district in the U.S. state of California. Barbara Lee, a Democrat, has represented this district since January 2013. The 13th district no longer consists of the northwestern port ...

(which includes western

and western

) . Current 10th district incumbent Josh Harder is running for reelection in the new version of California's 9th congressional district.

Election results from statewide races

1992 – 2021

Competitiveness

Voter Registration Statistics

The California Secretary of State publishes reports on California voter registration on a regular basis. Before the 2018 primary election, they published a report dating May 21, 2018.

Composition

As of the 2020 redistricting, California's 10th congressional district encompasses most of Contra Costa County, and part of

County. Contra Costa County is split between this district, the 8th district, and the 9th district. The northern border is partitioned by Grizzly Peak Blvd, Seaview Trail, Camino Pablo, Bear Creek Rd, San Pablo Creek, Bear Creek, Brianes Reservoir, Burlington Northern Santa Fe, Highway 4, Alhambra Ave, Pacheco Blvd, Grandview Ave, Central Ave, Imhoff Dr, Bares Ave, Mount Diablo Creek, Union Pacific, Contra Costa Canal, 4WD Rd, Bailey Rd, James Donlon Blvd, Cambridge Dr, Reseda Way, S Royal links Cir, Carpinteria Dr, Barmouth Dr, Hillcrest Ave, Highway 4, and Highway 160. The western border is partitioned by Old River, Italian Slough, Western Farms Ranch Rd, Rankin Rd, Highway J14, Byron Hot Springs Rd, Camino Diablo, Kellogg Creek, Sellers Ave, Brentwood Blvd, Alloro Dr, Ghiggeri Dr, Emilio Dr, Guthrie Ln, Balfour Rd, Chestnut St, Byron Highway, Orwood Rd, Burlington Northern Santa Fe, Werner Dredger Cut, and Rock Slough. The 10th district takes in the south sides of the cities of

and Martinez, the cities of

, Brentwood, Oakley, Pleasant Hill, Clayton,

Lafayette Lafayette or La Fayette may refer to: People * Lafayette (name), a list of people with the surname Lafayette or La Fayette or the given name Lafayette * House of La Fayette, a French noble family ** Gilbert du Motier, Marquis de Lafayette (1757� ...

, Orinda, and San Ramon, as well as the towns of Danville and Moraga. Alameda County is split between this district and the 14th district. They are partitioned by Sinclair Freeway, Amador Valley Blvd, Emerald Ave, Tamarack Dr, Brighton Dr, Ione Way, Newcastle Ln, Dougherty Rd, Highway 580, Lembert Hills Dr. The 10th district takes in San Ramon Village and Komandorski Village.

Cities & CDP with 10,000 or more people

- 129,295 *

- 115,291 * San Ramon - 84,605 *

- 70,127 * Brentwood - 64,292 * Danville - 43,582 * Oakley - 43,357 * Martinez - 38,290 * Pleasant Hill - 34,613 *

- 25,391 * Orinda - 19,514 * Moraga - 16,870 * Clayton - 11,070

List of members representing the district

Election results for representatives

1912

1914

1916 (Special)

1916

1918

1920

1922

1923 (Special)

John D. Fredericks won the special election to replace fellow Republican

Henry Z. Osborne Henry Zenas Osborne (October 4, 1848 – February 8, 1923) was an American Republican politician who served in the United States House of Representatives from 1917 to 1923. Biography He was born in New Lebanon, New York on October 4, 1848. I ...

, who died in office.

1924

1926

1928

1930

1932

1934

1936

1937 (Special)

Alfred J. Elliott won the special election to replace fellow Democrat

Henry E. Stubbs Henry Elbert Stubbs (March 4, 1881 – February 28, 1937) was an American clergyman and politician who served two terms as a U.S. Representative from California from 1933 to 1937. Biography Born in Nampa, Coleman County, Texas, Stubbs atte ...

, who died in office.

1938

1940

1942

1944

1946

1948

1950

1952

1954

1956

1958

1960

1962

1964

1966

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2009 (Special)

2010

2012

2014

2016

2018

2020

References

External links

* GovTrack.us
California's 10th congressional district

(out of date)
California Voter Foundation map - CD10
(out of date) {{DEFAULTSORT:California's 10th Congressional District 10 Government of San Joaquin County, California Government of Stanislaus County, California San Joaquin Valley Ceres, California Modesto, California Oakdale, California Tracy, California Turlock, California Constituencies established in 1913 1913 establishments in California