Contra Costa, California — Presidential Election Results
Contra Costa, California has voted Democratic in 7 of the last 7 presidential elections on record (2000–2024). In 2024, it was 18.5 pts more Dem. than California overall.
Jump to year: 2000 · 2004 · 2008 · 2012 · 2016 · 2020 · 2024
Full Election History, 2000–2024
| Year | Winner | Party | Votes | Vote Share | Margin | Total Votes Cast | Swing | Vs. California |
|---|---|---|---|---|---|---|---|---|
| 2000 | Al Gore | Democratic | 224,338 | 58.8% | 21.7 pts (82,965 votes) | 381,478 | — | 10.3 pts more Dem. |
| 2004 | John Kerry | Democratic | 257,254 | 62.4% | 25.9 pts (106,646 votes) | 412,139 | +3.5 pts | 16.0 pts more Dem. |
| 2008 | Barack Obama | Democratic | 306,983 | 68.0% | 37.8 pts (170,547 votes) | 451,650 | +12.3 pts | 13.9 pts more Dem. |
| 2012 | Barack Obama | Democratic | 290,824 | 66.4% | 35.2 pts (154,307 votes) | 438,226 | -2.4 pts | 12.4 pts more Dem. |
| 2016 | Hillary Clinton | Democratic | 319,287 | 68.5% | 43.6 pts (203,331 votes) | 466,175 | +10.6 pts | 14.5 pts more Dem. |
| 2020 | Joseph R Biden Jr | Democratic | 416,386 | 71.6% | 45.3 pts (263,509 votes) | 581,316 | -0.4 pts | 16.5 pts more Dem. |
| 2024 | Kamala D Harris | Democratic | 356,008 | 67.3% | 37.9 pts (200,700 votes) | 528,904 | -7.0 pts | 18.5 pts more Dem. |
Population Context
Total Census Bureau population estimate for the county that year, and recorded votes as a share of that total population. This is a population-based figure, not a turnout rate against eligible or registered voters, which this site does not calculate.
| Year | County Population | Votes Cast (% of Population) |
|---|---|---|
| 2000 | 952,810 | 40.0% of population |
| 2004 | 992,424 | 41.5% of population |
| 2008 | 1,023,344 | 44.1% of population |
| 2012 | 1,077,548 | 40.7% of population |
| 2016 | 1,137,268 | 41.0% of population |
| 2020 | 1,166,165 | 49.8% of population |
| 2024 | 1,172,607 | 45.1% of population |
Trend
Between 2000 and 2024, the two-party presidential margin in Contra Costa shifted 16.6 points toward the Democratic candidate, based on recorded county returns. This reflects the vote totals in this dataset only; no claim is made here about the causes of that shift.
Margin Over Time
Democratic candidate's margin (percentage points, two-party vote share). Positive values favor the Democratic candidate; negative values favor the Republican candidate.
Bellwether Status
Contra Costa has matched the national popular winner in 3 of the last 7 presidential elections (43%), and California's own statewide winner in 7 of 7 (100%). Compare every county on the bellwether counties page.
Related Pages
Other California Counties
Frequently Asked Questions
How has Contra Costa voted in presidential elections since 2000?
Since 2000, Contra Costa has voted Democratic in 7 of 7 recorded presidential elections and Republican in 0 of 7, based on county-level returns through 2024.
What was the closest presidential election in Contra Costa?
Contra Costa's closest recorded margin was in 2000, when Al Gore (Democratic) won by 22.7 points (82,965 votes) out of 381,478 total votes cast.
Has Contra Costa ever flipped between parties?
Not in the 2000-2024 record on this page -- Contra Costa has voted for the same party in every recorded presidential election in that span.
What is the largest presidential election margin recorded in Contra Costa?
The widest margin on record for Contra Costa was in 2016, when Hillary Clinton (Democratic) won by 46.7 points.
How many votes were cast in Contra Costa relative to its population?
In 2024, 528,904 votes were recorded in Contra Costa against a total population of 1,172,607 (45.1% of the total population). This is a population-based figure, not a turnout rate against eligible or registered voters, which this site does not calculate.
Is Contra Costa a presidential bellwether county?
Contra Costa has matched the national popular winner in 3 of the last 7 presidential elections (43%), and California's own statewide winner in 7 of 7 (100%).