Contra Costa County, CA
CA · Presidential Elections 1876–2024
Contra Costa County, CA (California) voted D+37.9 for Kamala Harris (Democrat) in the 2024 presidential election, with Harris receiving 356,008 votes (67.31%) to 155,308 (29.36%) for Trump.
This represents a R+7.4% swing toward Republicans compared to 2020. Contra Costa County is classified as a deep Democratic county. Contra Costa County has voted Democratic in every presidential election since 1988. The county has a population of approximately 1,165,012.
Quick Stats
Demographics
Community Profile
Religious Composition
Source: Religion Census 2020Ancestry Groups
Source: Census ACSTop reported ancestry groups (compared to national average).
Age Distribution
Employment by Industry
Census ACSPresidential Elections
Presidential Results
| Year | Democrat | Republican | Margin | Swing |
|---|---|---|---|---|
| 2024 | 67.3%(356,008) | 29.4%(155,308) | D+37.9 | R+7.4 |
| 2020 | 71.6%(416,386) | 26.3%(152,877) | D+45.3 | D+2.3 |
| 2016 | 67.5%(319,287) | 24.5%(115,956) | D+43.0 | D+7.8 |
| 2012 | 66.2%(290,824) | 31.1%(136,517) | D+35.1 | R+2.5 |
| 2008 | 67.7%(306,983) | 30.1%(136,436) | D+37.6 | D+11.8 |
| 2004 | 62.3%(257,254) | 36.5%(150,608) | D+25.8 | D+4.1 |
| 2000 | 58.8%(224,338) | 37.1%(141,373) | D+21.7 | D+1.2 |
| 1996 | 55.7%(196,512) | 35.1%(123,954) | D+20.6 | R+0.8 |
| 1992 | 50.9%(194,960) | 29.5%(112,965) | D+21.4 | D+18.2 |
| 1988 | 51.1%(169,411) | 47.9%(158,652) | D+3.2 | D+13.2 |
Source: Official state election returns via MIT Election Data + Science Lab
Presidential Margin Trend
Contra Costa County, CA • 1876–2024
Senate Elections
Senate Results
| Year | Democrat | Republican | Margin | Swing |
|---|---|---|---|---|
| 2024 | 67.5%(343,169) | 32.5%(165,245) | D+35.0 | R+63.2 |
| 2018 | 98.2%(374,190) | 0.0%(0) | D+98.2 | R+2.5 |
| 2016 | 100.7%(410,152) | 0.0%(0) | D+100.7 | D+60.6 |
| 2012 | 70.1%(300,194) | 29.9%(128,310) | D+40.1 | R+1.5 |
| 2006 | 68.5%(205,516) | 26.9%(80,764) | D+41.6 | D+13.2 |
| 2000 | 61.6%(232,109) | 33.2%(125,188) | D+28.4 | D+6.5 |
| 1994 | 57.9%(170,256) | 36.0%(105,854) | D+21.9 | R+9.1 |
| 1992 | 62.3%(229,988) | 31.3%(115,507) | D+31.0 | D+35.9 |
| 1988 | 46.2%(152,714) | 51.1%(168,760) | R+4.9 | D+3.5 |
| 1982 | 44.0%(110,813) | 52.3%(131,875) | R+8.4 | R+5.3 |
Source: Official state election returns via MIT Election Data + Science Lab
Governor Elections
Governor Results
| Year | Democrat | Republican | Margin | Swing |
|---|---|---|---|---|
| 2022 | 68.3%(265,371) | 31.7%(123,132) | D+36.6 | D+0.2 |
| 2018 | 68.2%(283,805) | 31.8%(132,345) | D+36.4 | R+0.9 |
| 2014 | 68.6%(174,403) | 31.4%(79,660) | D+37.3 | D+12.2 |
| 2010 | 60.6%(211,125) | 35.5%(123,606) | D+25.1 | D+35.1 |
| 2006 | 42.5%(128,578) | 52.4%(158,565) | R+9.9 | R+27.5 |
| 2002 | 53.2%(140,975) | 35.7%(94,487) | D+17.6 | R+11.0 |
| 1998 | 62.8%(190,200) | 34.2%(103,686) | D+28.6 | D+35.0 |
| 1994 | 45.0%(135,133) | 51.5%(154,482) | R+6.4 | R+15.4 |
| 1990 | 52.9%(144,268) | 43.9%(119,901) | D+8.9 | D+37.6 |
| 1986 | 34.7%(87,117) | 63.3%(159,105) | R+28.6 | R+26.0 |
Source: Official state election returns via MIT Election Data + Science Lab