| Election Name: | 2016 California State Senate election |
| Country: | California |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 2014 California State Senate election |
| Previous Year: | 2014 |
| Next Election: | 2018 California State Senate election |
| Next Year: | 2018 |
| Seats For Election: | 20 seats from odd-numbered districts in the California State Senate |
| Majority Seats: | 21 |
| Image1: | File:Kevin de León (portrait).jpg |
| Leader1: | Kevin de León |
| Party1: | California Democratic Party |
| Leaders Seat1: | 24th–Los Angeles |
| Seats Before1: | 26 |
| Seats After1: | 27 |
| Seat Change1: | 1 |
| Popular Vote1: | 4,769,557 |
| Percentage1: | 67.48% |
| Leader2: | Jean Fuller |
| Party2: | California Republican Party |
| Leaders Seat2: | 16th–Bakersfield |
| Seats Before2: | 14 |
| Seats After2: | 13 |
| Seat Change2: | 1 |
| Popular Vote2: | 2,250,103 |
| Percentage2: | 31.84% |
| Map Size: | 450px |
| President pro tempore | |
| Posttitle: | President pro tempore-designate |
| Before Election: | Kevin de León |
| Before Party: | California Democratic Party |
| After Election: | Kevin de León |
| After Party: | California Democratic Party |
The 2016 California State Senate election were held on Tuesday, November 8, 2016, with the primary election on June 7, 2016. Voters in the 20 odd-numbered districts of the California State Senate elected their representatives. The elections coincided with the elections for other offices, including for U.S. President and the state assembly.
Only one seat changed hands: the 29th district, which belonged to outgoing former Republican Minority Leader Bob Huff. As a result of the pickup by Democrat Josh Newman, the California Democratic Party regained a two-thirds supermajority in the chamber that it had previously lost in 2014.
| California State Senate elections, 2016 Primary election — June 7, 2016 | |||||||
|---|---|---|---|---|---|---|---|
| Party | Votes | Percentage | Candidates | Advancing to general | Seats contesting | ||
| Democratic | 2,724,063 | 66.59% | 42 | 25 | 20 | ||
| Republican | 1,353,572 | 33.09% | 25 | 14 | 14 | ||
| Libertarian | 13,065 | 0.32% | 2 | 1 | 1 | ||
| Totals | 4,090,700 | 100.00% | 69 | 40 | — | ||
| California State Senate elections, 2016 General election — November 8, 2016 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Party | Votes | Percentage | Not up | Contested | Before | After | +/– | ||
| Democratic | 4,769,557 | 67.48% | 11 | 15 | 26 | 27 | 1 | ||
| Republican | 2,250,103 | 31.84% | 9 | 5 | 14 | 13 | 1 | ||
| Libertarian | 48,316 | 0.68% | 0 | 0 | 0 | 0 | |||
| Totals | 7,067,976 | 100.00% | 20 | 20 | 40 | 40 | — | ||
| 27 | 13 | ||
| Democratic | Republican | ||
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