Elections were held inCalifornia on June 5, 2012. Twopropositions,primary elections for eachparty's nominee forPresident, primary elections to determine thetop-two candidates for California'sClass I seat to theUnited States Senate, all of California's seats to theHouse of Representatives, all of the seats of theState Assembly, and all odd-numbered seats of theState Senate, who went on to compete against each other in arun-off on November 6, 2012, were on the ballot.
This was the first election with California's newly implementednonpartisan blanket primary in effect, pursuant toProposition 14, which passed with 53% voter approval in June 2010. Additionally, in November 2010, voters approvedProposition 20, which authorized a CaliforniaCitizens Redistricting Commission to re-drawcongressional district lines, in addition to its current job of drawingstate senate district lines andstate assembly district lines, taking away that job from theCalifornia state legislature. This was the first election which used the Citizens Redistricting Commission's maps.
Incumbent presidentBarack Obama ran unopposed on the Democratic primary ballot. GovernorMitt Romney and Rep.Ron Paul competed in theRepublican primary.

| California Republican primary, 2012[1] | |||
|---|---|---|---|
| Candidate | Votes | Percentage | Delegates |
| 1,151,197 | 79.6% | 169 | |
| Ron Paul | 147,893 | 10.2% | 0 |
| Rick Santorum | 75,802 | 5.2% | 0 |
| Newt Gingrich | 55,458 | 3.8% | 0 |
| Buddy Roemer | 9,714 | 0.7% | 0 |
| Fred Karger | 6,481 | 0.4% | 0 |
| Unpledged delegates: | 3 | ||
| Total: | 1,446,545 | 100% | 172 |
| Key: | Withdrew prior to contest |

| Party | Candidate | Votes | % | |
|---|---|---|---|---|
| Democratic | Dianne Feinstein (Incumbent) | 1,801,422 | 49.3 | |
| Republican | Elizabeth Emken | 454,937 | 12.5 | |
| Republican | Dan Hughes | 243,934 | 6.7 | |
| Republican | Rick Williams | 120,931 | 3.3 | |
| Republican | Orly Taitz | 113,563 | 3.1 | |
| Republican | Dennis Jackson | 107,097 | 2.9 | |
| Republican | Greg Conlon | 100,432 | 2.8 | |
| Republican | Al Ramirez | 82,663 | 2.3 | |
| Libertarian | Gail Lightfoot | 76,130 | 2.1 | |
| Democratic | Diane Stewart | 74,358 | 2.0 | |
| Other | Others | 475,150 | 13.0 | |
| Total votes | 3,650,617 | 100 | ||
100% ( 21,993 of 21,993 ) precincts partially or fully reporting as of June 22, 2012, 4:49 p.m

Proposition 28 is an initiative constitutional amendment that would changeCalifornia state legislature term limits from a limit of 8 years for theSenate and 6 years for theAssembly, to a limit of 12 years on combined service.
| Choice | Votes | % |
|---|---|---|
| 3,001,137 | 61.0 | |
| No | 1,915,154 | 39.0 |
| Total votes | 4,916,291 | 100.00 |
| Registered voters/turnout | 23,713,027 | 20.7 |

Proposition 29 is an initiative statute that would add a $1 tax oncigarettes to fund cancer research.
| Choice | Votes | % |
|---|---|---|
| 2,553,137 | 50.3 | |
| Yes | 2,523,572 | 49.7 |
| Total votes | 5,025,120 | 100.00 |
| Registered voters/turnout | 23,713,027 | 21.2 |