Contra Costa County, California
AkashicContra Costa County, CAHarrisD+37.9
2024 precinct map of Contra Costa CountyPrecinct-level 2024 presidential results for Contra Costa County, with each precinct boundary colored by Democratic-vs-Republican margin, and gold where an independent or third-party candidate carried the precinct.
How it voted
Share of the 2024 vote
| Kamala Harris ✓Democratic | 67.3% | 356,008 |
|---|---|---|
| Donald TrumpRepublican | 29.4% | 155,308 |
| Jill SteinGreen | 1.3% | 6,691 |
Harris +50Trump +50
674 precincts · 528,904 votes. Hover any precinct for its result.
The precinct map shows the 2024 presidential vote; the timeline scrubs the county’s overall result across 1876–2024.
38 presidential elections
| Year | Won | Democratic | Republican | Other | Margin | Total |
|---|---|---|---|---|---|---|
| D | 67.3%Harris356,008 | 29.4%Trump155,308 | 1.3%Stein6,691 | 528,904 | ||
| D | 71.6%Biden416,386 | 26.3%Trump152,877 | 1.1%Jorgensen6,116 | 581,316 | ||
| D | 67.5%Clinton319,287 | 24.5%Trump115,956 | 3.4%Johnson16,123 | 473,014 | ||
| D | 66.2%Obama290,824 | 31.1%Romney136,517 | 1.0%Johnson4,372 | 439,145 | ||
| D | 67.7%Obama306,983 | 30.1%McCain136,436 | 2.2%Nader9,825 | 453,244 | ||
| D | 62.3%Kerry257,254 | 36.5%Bush150,608 | 1.3%Badnarik5,166 | 413,028 | ||
| D | 58.8%Gore224,338 | 37.1%Bush141,373 | 3.4%Nader13,067 | 381,478 | ||
| D | 55.7%Clinton196,512 | 35.2%Dole123,954 | 5.8%Perot20,416 | 352,602 | ||
| D | 50.9%Clinton194,960 | 29.5%Bush112,965 | 18.9%Perot72,518 | 382,823 | ||
| D | 51.1%Dukakis169,411 | 47.9%Bush158,652 | 1.0%Paul3,448 | 331,511 | ||
| R | 44.6%Mondale140,994 | 54.5%Reagan172,331 | 0.9%Bergland2,993 | 316,318 | ||
| R | 37.3%Carter107,398 | 50.1%Reagan144,112 | 12.5%Anderson36,035 | 287,545 | ||
| R | 48.2%Carter123,742 | 49.3%Ford126,598 | 2.4%Macbride6,194 | 256,534 | ||
| R | 43.5%McGovern111,718 | 54.1%Nixon139,044 | 2.4%Schmitz6,122 | 256,884 | ||
| D | 46.4%Humphrey101,668 | 44.5%Nixon97,486 | 9.0%Wallace19,763 | 218,917 | ||
| D | 63.4%Johnson113,071 | 36.5%Goldwater65,011 | 0.1%Hass163 | 178,245 | ||
| D | 52.9%Kennedy93,622 | 46.8%Nixon82,922 | 0.3%Byrd579 | 177,123 | ||
| R | 48.8%Stevenson71,733 | 51.0%Eisenhower74,971 | 0.2%Andrews347 | 147,051 | ||
| D | 50.3%Stevenson69,060 | 49.1%Eisenhower67,453 | 0.6%Hallinan768 | 137,281 | ||
| D | 55.0%Truman50,277 | 40.4%Dewey36,958 | 4.5%Thurmond4,141 | 91,376 | ||
| D | 64.0%Roosevelt47,831 | 35.9%Dewey26,816 | 0.2%Thomas138 | 74,785 | ||
| D | 61.8%Roosevelt30,900 | 37.2%Willkie18,627 | 1.0%Thomas513 | 50,040 | ||
| D | 72.3%Roosevelt26,007 | 26.7%Landon9,604 | 1.0%Lemke364 | 35,975 | ||
| D | 58.9%Roosevelt17,218 | 37.3%Hoover10,907 | 3.7%Thomas1,089 | 29,214 | ||
| R | 38.4%Smith8,573 | 60.4%Hoover13,495 | 1.3%Thomas281 | 22,349 | ||
| R | 6.7%Davis1,114 | 54.7%Coolidge9,061 | 38.6%La Follette6,398 | 16,573 | ||
| R | 24.6%Cox3,483 | 63.7%Harding9,041 | 11.7%Debs1,658 | 14,182 | ||
| D | 46.8%Wilson6,092 | 44.0%Hughes5,731 | 9.1%Benson1,188 | 13,011 | ||
| O | 39.4%Wilson3,290 | 0.0%Taft0 | 60.6%Roosevelt5,060 | 8,350 | ||
| R | 29.1%Bryan1,599 | 60.6%Taft3,336 | 10.3%Debs569 | 5,504 | ||
| R | 27.8%Parker1,257 | 62.6%Roosevelt2,833 | 9.7%Debs439 | 4,529 | ||
| R | 40.8%Bryan1,549 | 57.0%McKinley2,165 | 2.2%Woolley83 | 3,797 | ||
| R | 42.2%Bryan1,381 | 56.1%McKinley1,834 | 1.7%Palmer54 | 3,269 | ||
| R | 42.3%Cleveland1,332 | 51.8%Harrison1,631 | 5.9%Weaver186 | 3,149 | ||
| R | 42.7%Cleveland1,177 | 55.0%Harrison1,518 | 2.3%Fisk63 | 2,758 | ||
| R | 41.6%Cleveland1,114 | 55.9%Blaine1,496 | 2.5%Butler68 | 2,678 | ||
| R | 43.7%Hancock1,010 | 56.3%Garfield1,302 | 0.0% | 2,312 | ||
| R | 41.4%Tilden837 | 58.6%Hayes1,184 | 0.0% | 2,021 |
presidential history
Presidential margin, 1876–2024
Democratic minus Republican, by election
| Year | Margin (D minus R) |
|---|---|
| 1876 | −17.2% |
| 1880 | −12.6% |
| 1884 | −14.3% |
| 1888 | −12.4% |
| 1892 | −9.5% |
| 1896 | −13.9% |
| 1900 | −16.2% |
| 1904 | −34.8% |
| 1908 | −31.6% |
| 1912 | +39.4% |
| 1916 | +2.8% |
| 1920 | −39.2% |
| 1924 | −48.0% |
| 1928 | −22.0% |
| 1932 | +21.6% |
| 1936 | +45.6% |
| 1940 | +24.5% |
| 1944 | +28.1% |
| 1948 | +14.6% |
| 1952 | +1.2% |
| 1956 | −2.2% |
| 1960 | +6.0% |
| 1964 | +27.0% |
| 1968 | +1.9% |
| 1972 | −10.6% |
| 1976 | −1.1% |
| 1980 | −12.8% |
| 1984 | −9.9% |
| 1988 | +3.2% |
| 1992 | +21.4% |
| 1996 | +20.6% |
| 2000 | +21.7% |
| 2004 | +25.8% |
| 2008 | +37.6% |
| 2012 | +35.1% |
| 2016 | +43.0% |
| 2020 | +45.3% |
| 2024 | +37.9% |
DemocraticRepublican
voter registration
Registered voters
By party of registration, over time
DemocraticRepublicanUnaffiliatedOther parties
| Year | Total registered | Democratic | Republican | Unaffiliated | Other |
|---|---|---|---|---|---|
| 2022 | 699,475 | 376,247 | 127,301 | 155,235 | 40,692 |
| 2024 | 714,337 | 379,715 | 134,743 | 153,965 | 45,914 |
Source: California Secretary of State
Once a bellwether of white working-class suburban politics, Contra Costa has shifted decisively leftward over three decades as the population diversified and Bay Area commuter culture extended eastward into its inland cities.
Across the recorded series it reached a Democratic high of 45.6 points in 1936 and a Republican high of 48.0 points in 1924. Between 2020 and 2024 the county moved 7.4 points toward the Republican candidate; the 2024 margin was 37.9 points.
A population of 1,165,012, a 38% non-Hispanic-white share, and a median household income of $127,229 describe the county. The county's voting pattern over the last decade is most similar to that of Montgomery County and Santa Clara County.
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All citations released under CC BY 4.0. Attribution: Akashic Intelligence.
Contra Costa County, California. Akashic. https://akashic.app/county/06013/. Accessed May 20, 2026. License: CC BY 4.0.
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Frequently asked questions
How did Contra Costa County, California vote in 2024?
In 2024, Contra Costa County, California voted Democratic by 37.9 points (D+37.9), carried by the Democratic candidate. Out of 528,904 votes cast, 356,008 went Democratic and 155,308 went Republican.
When did Contra Costa County, California last vote Republican?
The most recent presidential election in which Contra Costa County, California voted Republican was 1984.
How many people live in Contra Costa County, California?
Contra Costa County, California has a population of 1,165,012 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in Contra Costa County, California?
Median household income in Contra Costa County, California is $127,229 — above the national median of $80,734. The California state median is $99,122.
What is the political history of Contra Costa County, California?
Akashic tracks 38 presidential elections in Contra Costa County, California from 1876 to 2024. Of those, 20 went Democratic and 17 went Republican.