Contra Costa County, CA — Elections & Voting
Presidential election results and party lean trends
Election Overview
Source: Contra Costa County (2024)2024 Winner
Democrat
Dem Votes
356,008
67.3%
GOP Votes
155,308
29.4%
Total Votes
528,904
Margin
D+38.0%
Shift from 2020
R+7.4pp
vs prior election
📊Election Results by Year
2016–2024📈Partisan Lean Trend
D+38.0%Election History
Source: County-Level Election Results| Year | Dem Votes | GOP Votes | Total | Dem % | GOP % | Margin |
|---|---|---|---|---|---|---|
| 2024 | 356,008 | 155,308 | 528,904 | 67.3% | 29.4% | D+38.0 |
| 2020 | 416,386 | 152,877 | 581,230 | 71.6% | 26.3% | D+45.3 |
| 2016 | 286,658 | 105,819 | 415,972 | 68.9% | 25.4% | D+43.5 |
In the 2024 presidential election, Contra Costa County recorded 528,904 total votes. Democrats won the county with 67.3% of the vote compared to 29.4% for Republicans, a margin of D+38.0%. Compared to 2020, the margin shifted R+7.4pp from the previous election. Since 2016, Contra Costa County has shifted 5.5 percentage points toward Republicans.