Under California's non-partisan blanket primary law, all candidates appear on the same ballot, regardless of party. In the primary, voters may vote for any candidate, regardless of their party affiliation. In the California system, the top two finishers — regardless of party — advance to the general election in November, even if a candidate receives a majority of the votes cast in the primary election. Washington and Louisiana have similar "jungle primary" style processes for U.S. Senate elections, as does Mississippi for U.S. Senate special elections.
The candidate filing deadline was March 8, 2018, and the primary election was held on June 5, 2018.[1]
DemocraticincumbentDianne Feinstein won re-election in 2012 with 63% of the vote, taking the record for the most popular votes in any U.S. Senate election in history, with 7.86 million votes.[2] Feinstein, at the time, was the ranking member of the Senate Judiciary Committee. She turned 85 years old in 2018, leading some to speculate that she would retire in January 2019,[3][4] as her long-time colleague Barbara Boxer did in January 2017. However, Feinstein ran for reelection to her fifth full term, winning 44.2% of the vote in the top-two primary; she faced Democratic challenger Kevin de León in the general election, who won 12.1% of the primary vote.[5] For the second time since direct elections to the Senate began after the passage of the Seventeenth Amendment in 1913, no Republican appeared on the general election ballot for U.S. Senate in California. The highest Republican finisher in the primary won only 8.3 percent of the vote, and the 10 Republicans only won 31.2 percent of the vote among them.
In the general election, Feinstein defeated de León by an eight-point margin, 54% to 46%. This was Feinstein's closest election since 1994, as well as her last run for elected office, as she died in office in September 2023.[6]
^ abNo ballot access: Constitution Party and Socialist Equality Party. Don J. Grundmann (C) and David Moore (SEP) appear on ballot as "No party preference".[26]
Stelian Onufrei, small business owner and former Republican candidate for California's 48th congressional district[105]
Robert "Buzz" Patterson, retired USAFLieutenant Colonel and author of Dereliction of Duty: The Eyewitness Account of How Bill Clinton Compromised America's National Security (2003)[106]
Because of California's top-two runoff system, the seat was guaranteed to be won/held by a Democrat since the initial primary produced two Democratic candidates.
The race had an undervote of around 1.3 million votes compared to the gubernatorial election, likely by Republican voters choosing neither candidate. De León won many of the same counties and congressional districts won by Republican gubernatorial nominee John Cox, as many voters may have expressed opposition to the incumbent senator. No county voted for both Feinstein and Cox. Congressional districts 39, 45, and 48 were the only congressional districts that voted for both Feinstein and Cox.[144][145]
Results by countyedit
Results by county. Blue represents counties won by Feinstein. Cyan represents counties won by de León.[146]
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^LeBlanc, Clare Foran,Paul (September 29, 2023). "Dianne Feinstein, longest-serving female US senator in history, dies at 90 | CNN Politics". CNN. Retrieved November 7, 2023.{{cite web}}: CS1 maint: multiple names: authors list (link)
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^"Laguna Beach Local News Laguna Local to Make a Bid for the Senate". Laguna Beach Local News. January 18, 2018. Retrieved April 4, 2018.
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^ abcdefghij"Dianne Feinstein, 84, is seeking another Senate term. Who might challenge her?". DailyNews.com. October 9, 2017. Retrieved January 20, 2018.
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^ ab"Nancy Pelosi endorses Dianne Feinstein for re-election to Senate, heading off possible primary challengers". Fox News. October 31, 2017.
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^ ab"Gov. Jerry Brown endorses Sen. Dianne Feinstein". Los Angeles Times. April 10, 2018. Retrieved April 18, 2018.
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^ abCadelago, Christopher (October 20, 2017). "Steinberg chooses Feinstein in 'difficult' decision". The Sacramento Bee.
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^ abPalmer Report (February 25, 2018). "Palmer Report endorses Dianne Feinstein in the Democratic primary. She's spent decades skillfully using her seat to move America to the left. Her primary opponent is well intentioned, but purist progressive foot stompers rarely deliver actual progress for the left". Twitter.com. Retrieved April 4, 2018.
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^ ab"Billionaire Democratic activist Tom Steyer endorses Kevin de Leon in his insurgent bid against Sen. Dianne Feinstein". Los Angeles Times. April 18, 2018. Retrieved April 19, 2018.
^ abDe Leon, Kevin (October 15, 2017). "Rep. Jimmy Gomez Endorses Kevin de León for U.S. Senate" (PDF). Los Angeles Times.
^ ab"Kevin de León announces run against Dianne Feinstein, setting up Democratic clash in Senate race". The Mercury News. October 15, 2017.
^ abcdefghMehta, Seema; Mason, Melanie (October 15, 2017). "California Senate leader Kevin de León announces he will challenge Sen. Dianne Feinstein". Los Angeles Times.
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^ abTolan, Casey (July 14, 2018). "California Democratic Party endorses De León for Senate, in rebuke for Feinstein". Mercury News. Retrieved July 14, 2018.
^ ab"Armenian Committee endorses Kevin de León for U.S. Senate". January 9, 2018. Retrieved January 9, 2018.
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^ ab"Gavin Newsom, Kevin de León win backing of major California labor group". San Francisco Chronicle. April 17, 2018.
^ abcdMehta, Seema (February 14, 2018). "Kevin de León boosted by back-to-back union endorsements in Senate bid against Sen. Dianne Feinstein". Los Angeles Times. Retrieved February 15, 2018.
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^Prins, Nomi [@nomiprins] (April 12, 2018). "Alison @HartsonForCA is the real deal. Not politics as usual, not co-opted by special interests and corporations, but dedicated to using public service to level the economic playing field for all Californians and Americans. https://t.co/XCucX6tUJa" (Tweet). Retrieved February 22, 2022 – via Twitter.
^Martin, Abby [@AbbyMartin] (May 19, 2018). "California voters have an open primary June 5th but still need to register by Monday. I'm excited to vote for progressive @HartsonForCA to replace Feinstein, socialist @GloriaLaRiva for Governor, @peaceandfreedom's Kevin Akin for Treasurer https://t.co/2bpLD0pSqs" (Tweet). Archived from the original on December 5, 2020. Retrieved February 22, 2022 – via Twitter.
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^Paul Taylor (R) 4%, Other Republicans 9%, Other Democrats 6%, All other candidates 2%, Undecided 25%
^Paul Taylor (R) with 2%; Adrienne Nicole Edwards (D), David Hildebrand (D), Herbert Peters (D), Douglas Howard Pierce (D), Arun Bhumitra (R), Jack Crew (R), Kevin Mottus (R), Mario Nabliba (R), Tom Palzer (R), Derrick Michael Reid (L), Ling Ling Shi (NPP), none of the above with 1%; all other candidates 0%; Undecided with 23%
^Arun Bhumitra (R) 4%; Jack Crew (R) 3%; Adrienne Nicole Edwards (D), Don J. Grundmann (C), Kevin Mottus (R), Tom Palzer (R), Douglas Howard Pierce (D), Derrick Michael Reid (L), and Paul Taylor (R) with 1%; Colleen Shea Fernald (NPP), Rash Ghosh (NPP), Tim Gildersleeve (NPP), Michael Fahmy Girgis (NPP), Jason Hanania (NPP), David Hildebrand (D), Jerry Laws (R), David Moore (SEP), Mario Nabliba (R), Lee W. Olson (NPP), John Thompson Parker (PFP), Herbert Peters (D), Gerald Plummer (D), Ling Ling Shi (NPP), Donnie Turner (D) with 0%; Undecided with 21%
^Herbert Peters (D), Douglas Howard Pierce (D), Donnie Turner (D), Derrick Michael Reid (L), John Thompson Parker (PFP), Arun Bhumitra (R), Jerry Laws (R), Mario Nabliba (R), Paul Taylor (R), and David Moore (SEP) with 1%; Adrienne Nicole Edwards (D), David Hildebrand (D), Gerald Plummer (D), Jack Crew (R), Kevin Mottus (R), Tom Palzer (R), Colleen Shea Fernald (NPP), Rash Ghosh (NPP), Tim Gildersleeve (NPP), Michael Fahmy Girgis (NPP), Don J. Grundmann (C), Jason Hanania (NPP), Lee W. Olson (NPP), and Ling Ling Shi (NPP) with 0%; Other 0%; Not voting 0%; Undecided with 41%
^Alison Hartson (D) with 3%David Hildebrand (D) 2%; Donald Adams (R), Jerry Leon Carroll (NPP), Pat Harris (D), Richard Mead (NPP), Douglas Howard Pierce (D), Steve Stokes (D), and Michael Ziesing (G, write-in) with 1%; Clifton Roberts (H) 0%; Other with 1%; Undecided with 29%
^Alison Hartson (D) with 3%; Pat Harris (D), David Hildebrand (D), Clifton Roberts (H), Steve Stokes (D), and Michael Ziesing (G, write-in) with 1%; Donald Adams (R), Jerry Leon Carroll (NPP), Michael Eisen (NPP), Tim Gildersleeve (NPP), Charles Junior Hodge (NPP), Richard Mead (NPP), and Douglas Howard Pierce with 0%; Undecided with 30%
^Stephen Schrader (R) 4%; Pat Harris (D), Alison Hartson (D), John Melendez (D), and Michael Ziesing (G, write-in) with 2%; David Hildebrand (D) and Steve Stokes (D) with 1%; Donald Adams (R), Jery Leon Carroll (NPP), Michael Eisen (NPP), Tim Gildersleeve, Charles Junior Hodge (NPP), Richard Mead (NPP), Douglas Howard Pierce (D), and Clifton Roberts (H) with 0%; Undecided with 30%
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