| President Democratic - District 12 | 100.% ( 383 of 383 ) precincts reporting as of Mar 4, 2008, at 9:49 a.m. County Returns Other Contests | | San Mateo County Results | |
| |
| | Joe Biden (Dem) | 320 | 0.3 % |   |
| | Dennis Kucinich (Dem) | 395 | 0.4 % |   |
| | Barack Obama (Dem) | 42,051 | 43.2 % |   |
| | Bill Richardson (Dem) | 247 | 0.2 % |   |
| | Hillary Clinton (Dem) | 50,364 | 51.8 % |   |
| | Chris Dodd (Dem) | 112 | 0.1 % |   |
| | John Edwards (Dem) | 3,739 | 3.9 % |   |
| | Mike Gravel (Dem) | 113 | 0.1 % |   |
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