| President Republican | 100.% ( 816 of 816 ) precincts reporting as of Mar 4, 2008, at 9:49 a.m. County Returns Other Contests | | Contra Costa County Results | |
| |
| | Mike Huckabee (Rep) | 7,959 | 9.4 % |   | 328,387 | 11.6 % |   |
| | Duncan Hunter (Rep) | 166 | 0.1 % |   | 13,682 | 0.4 % |   |
| | Alan Keyes (Rep) | 295 | 0.3 % |   | 11,362 | 0.4 % |   |
| | Sam Brownback (Rep) | 56 | 0.0 % |   | 2,426 | 0.0 % |   |
| | John H. Cox (Rep) | 63 | 0.0 % |   | 3,101 | 0.1 % |   |
| | Rudy Giuliani (Rep) | 5,182 | 6.2 % |   | 126,415 | 4.5 % |   |
| | John McCain (Rep) | 41,107 | 48.5 % |   | 1,197,757 | 42.3 % |   |
| | Ron Paul (Rep) | 2,958 | 3.5 % |   | 120,374 | 4.3 % |   |
| | Mitt Romney (Rep) | 24,948 | 29.5 % |   | 980,969 | 34.6 % |   |
| | Tom Tancredo (Rep) | 104 | 0.1 % |   | 3,810 | 0.1 % |   |
| | Fred Thompson (Rep) | 1,993 | 2.4 % |   | 49,318 | 1.7 % |   |
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