| Election Name: | 2002 California State Senate election |
| Country: | California |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 2000 California State Senate election |
| Previous Year: | 2000 |
| Next Election: | 2004 California State Senate election |
| Next Year: | 2004 |
| Seats For Election: | 20 seats from even-numbered districts in the California State Senate |
| Majority Seats: | 21 |
| Leader1: | John Burton |
| Party1: | California Democratic Party |
| Leaders Seat1: | 3rd–San Francisco |
| Seats Before1: | 26 |
| Seats After1: | 25 |
| Seat Change1: | 1 |
| Popular Vote1: | 1,635,495 |
| Percentage1: | 53.78% |
| Leader2: | Jim Brulte |
| Party2: | California Republican Party |
| Leaders Seat2: | 31st–Rancho Cucamonga |
| Seats Before2: | 14 |
| Seats After2: | 15 |
| Seat Change2: | 1 |
| Popular Vote2: | 1,323,777 |
| Percentage2: | 43.53% |
| Map Size: | 450px |
| President pro tempore | |
| Posttitle: | President pro tempore-designate |
| Before Election: | John L. Burton |
| Before Party: | California Democratic Party |
| After Election: | John L. Burton |
| After Party: | California Democratic Party |
The 2002 California State Senate elections were held on November 5, 2002. Senate seats of even-numbered districts were up for election. Senate terms are staggered so that half the membership is elected every two years. Senators serve four-year terms and are limited to two terms. As was expected, the Democratic Party held on to the majority of the seats, though they lost one.
| California State Senate elections, 2002 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Party | Votes | Percentage | Not up | Incumbents | Open | Before | After | +/– | ||
| Democratic | 1,635,495 | 53.78% | 12 | 11 | 3 | 26 | 25 | -1 | ||
| Republican | 1,323,777 | 43.53% | 8 | 3 | 3 | 14 | 15 | +1 | ||
| Libertarian | 76,243 | 2.51% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Independent | 5,635 | 0.19% | 0 | 0 | 0 | 0 | 0 | 0 | ||
| Invalid or blank votes | 310,379 | 9.26% | — | — | — | — | — | — | ||
| Totals | 3,351,529 | 100.00% | 20 | 14 | 6 | 40 | 40 | — | ||
Final results from the California Secretary of State:[1]
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