Presidential elections · 2000–2024
Contra Costa County, CA — Presidential Election Results (2000–2024)
In 2024, Contra Costa County, California voted for Kamala D. Harris (Democratic) by D+37.9 — 356,008 Democratic to 155,308 Republican of 528,904 votes cast. From 2020 to 2024 it shifted 7.4 points toward Republicans. That makes it 17.8 points more Democratic than California overall (D+20.1).
Data: MIT Election Data & Science Lab, Harvard Dataverse.
Margin by election, 2000–2024
Democratic minus Republican, in points of all votes cast — blue bars Democratic, red Republican.
Every election in Contra Costa County
| Year | Democratic | Republican | Other | Dem share | Rep share | Margin |
|---|---|---|---|---|---|---|
| 2024 | 356,008 | 155,308 | 17,588 | 67.3% | 29.4% | D+37.9 |
| 2020 | 416,386 | 152,877 | 12,053 | 71.6% | 26.3% | D+45.3 |
| 2016 | 319,287 | 115,956 | 30,932 | 68.5% | 24.9% | D+43.6 |
| 2012 | 290,824 | 136,517 | 10,885 | 66.4% | 31.2% | D+35.2 |
| 2008 | 306,983 | 136,436 | 8,231 | 68.0% | 30.2% | D+37.8 |
| 2004 | 257,254 | 150,608 | 4,277 | 62.4% | 36.5% | D+25.9 |
| 2000 | 224,338 | 141,373 | 15,767 | 58.8% | 37.1% | D+21.7 |
Contra Costa County presidential elections — FAQ
Who carried Contra Costa County in the 2024 presidential election?+
Kamala D. Harris (Democratic) carried Contra Costa County, California in 2024 by D+37.9, with 528,904 votes cast. Data: MIT Election Data & Science Lab.
How did Contra Costa County shift between 2020 and 2024?+
Contra Costa County shifted 7.4 points toward Republicans between 2020 (D+45.3) and 2024 (D+37.9).
Is Contra Costa County more Democratic or Republican than California overall?+
In 2024, Contra Costa County went D+37.9 while California overall went D+20.1 — 17.8 points more Democratic than the state.
Where does this election data come from?+
County-level presidential returns (2000–2024) come from the MIT Election Data and Science Lab (MEDSL), published on the Harvard Dataverse. pumsdata is an independent product that makes the data easy to map and compare, and is not affiliated with MEDSL or Harvard.