San Mateo County, California
Votes
Percentages
| Year | Democrat | Republican | Other | Total | |||
|---|---|---|---|---|---|---|---|
| 2000 | 166,757 | 64.3% | 80,296 | 31.0% | 12,346 | 4.8% | 259,399 |
| 2004 | 197,922 | 69.7% | 83,315 | 29.3% | 2,840 | 1.0% | 284,077 |
| 2008 | 222,826 | 73.5% | 75,057 | 24.7% | 5,409 | 1.8% | 303,292 |
| 2012 | 206,085 | 72.1% | 72,756 | 25.5% | 6,879 | 2.4% | 285,720 |
| 2016 | 237,882 | 75.7% | 57,929 | 18.4% | 18,573 | 5.9% | 314,384 |
| 2020 | 291,496 | 77.9% | 75,584 | 20.2% | 7,171 | 1.9% | 374,251 |