The 2018 United States Senate election in California took place on November 6, 2018, to elect a member of the United States Senate to represent California, concurrently with other elections to the United States Senate, elections to the United States House of Representatives, and various state and local elections.

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.

Democratic incumbent Dianne 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. 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, as her long-time colleague Barbara Boxer did in January 2017. However, Feinstein ran for re-election 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. 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 the 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. Briefly, during the early stages of the primary, Patrick Little, a Neo-Nazi running as a Republican polled at 18% which at the time put him in second place and the likely runoff candidate against Feinstein, however, his campaign collapsed after the media reported on his views.

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.

Candidates Democratic Party Advanced to general Kevin de León, President pro tempore of the California State Senate Dianne Feinstein, incumbent U.S. Senator

Eliminated in primary Adrienne Nicole Edwards, Vice Chairwoman on the HDT Community Development Foundation board Pat Harris, attorney Alison Hartson, national director of Wolf PAC David Hildebrand, legislative analyst Herbert G. Peters, retired aerospace engineer and candidate for U.S. Senate in California in 2016 Douglas Howard Pierce Gerald Plummer Donnie O. Turner, Air Force veteran

Withdrawn Topher Brennan John Melendez, television writer and radio personality Steve Stokes, candidate for the U.S. Senate in 2016

Declined Ana Kasparian, co-host of The Young Turks Joe Sanberg, entrepreneur and investor Tom Steyer, hedge fund manager Cenk Uygur, host of The Young Turks

Republican Party Declared Arun K. Bhumitra, businessman James P. Bradley, businessman Jack Crew, bus driver Erin Cruz, published author Rocky De La Fuente, entrepreneur and perennial candidate Jerry Joseph Laws, candidate for the U.S. Senate in 2016 Patrick Little, neo-Nazi and Holocaust denier (denounced by California Republican Party) Kevin Mottus, candidate for the U.S. Senate in 2016 Mario Nabliba, scientist Tom Palzer, activist, retired city planner and candidate for the U.S. Senate in 2016 Paul Allen Taylor, businessman

Withdrawn

Donald R. Adams, businessman Gary Coson John Estrada Timothy Charles Kalemkarian, perennial candidate Ernie Konnyu, former U.S. Representative Caren Lancona, businesswoman Jazmina Saavedra, businesswoman and activist Stephen James Schrader, veteran

Declined Kevin Faulconer, mayor of San Diego Caitlyn Jenner, 1976 Olympic gold medalist and television personality Arnold Schwarzenegger, actor and former Governor of California Ashley Swearengin, former mayor of Fresno

Libertarian Party Declared Derrick Michael Reid, retired attorney and engineer and candidate for president in 2016

Green Party Declared Michael V. Ziesing (write-in)

Peace and Freedom Party Declared John Thompson Parker

No party preference Declared Colleen Shea Fernald, perennial candidate Rash Bihari Ghosh Tim Gildersleeve, businessman and researcher Michael Fahmy Girgis Don J. Grundmann, California Constitution Party chairman and perennial candidate (Constitution Party) Jason M. Hanania David Moore (Socialist Equality Party) Lee W. Olson Ursula M. Schilling (write-in) Ling Ling Shi, evangelist

Withdrawn Jerry Leon Carroll Michael Eisen, biologist Charles Junior Hodge Richard Thomas Mead Clifton Roberts (Humane Party)

Notes

Primary election Endorsements

Fundraising Campaign finance reports as of May 16, 2018CandidateTotal receiptsTotal disbursementsCash on handDianne Feinstein (D)$9,953,612$5,342,658$7,035,307Kevin de León (D)$1,135,538$441,847$693,689Pat Harris (D)$703,982$650,225$51,017Alison Hartson (D)$298,296$189,652$108,643Arun K. Bhumitra (R)$53,668$40,835$12,832David Hildebrand (D)$27,111$25,816$1,294Erin Cruz (R)$26,442$23,190$3,251Douglas Howard Pierce (D)$9,000$62,392$11,200Paul Allen Taylor (R)$9,128$8,803$324Tom Palzer (R)$0$45$45David Moore (SEP)$3,480$3,480$0Source: Federal Election Commission

Polling Poll source Date(s)administered Samplesize Margin James P.Bradley(R) ErinCruz(R) PatHarris(D) Rocky De(R) Kevinde León(D) DianneFeinstein(D) AlisonHartson(D) PatrickLittle(R) Other /UndecidedUC BerkeleyUC Berkeley May 22−28, 2018 2,106 ± 3.5% 7% – – – 11% 36% – – 46%Paul Taylor (R) 4%, Other Republicans 9%, Other Democrats 6%, All other candidates 2%, Undecided 25%Emerson CollegeEmerson College May 21–24, 2018 600 ± 4.2% – 5% 6% 4% 6% 38% 4% – 38%Other 6%, Undecided 32%YouGovYouGov May 12–24, 2018 1,113 ± 4.0% 6% 2% 2% 4% 11% 36% 1% 1% 37%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%SurveyUSASurveyUSA May 21, 2018 678 ± 6.1% 9% 2% 2% 3% 11% 36% 1% 0% 35%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%Public Policy Institute of CaliforniaPublic Policy Institute of California May 11–20, 2018 901 ± 4.1% – – – – 17% 41% – – 41%Other with 5%, Undecided with 36%USC Dornsife/Los Angeles TimesUSC Dornsife/Los Angeles Times April 18 – May 18, 2018 517 ± 4.0% 3% 1% 2% 0% 7% 31% 1% 2% 51%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%Gravis MarketingGravis Marketing May 4–5, 2018 525 ± 4.3% 19% 13% – – 8% 32% 6% – 21%John Melendez* (D) 3%, David Hildebrand (D) 2%, Undecided 16%. *WithdrawnSurveyUSASurveyUSA April 19–23, 2018 520 ± 5.5% – – – 8% 8% 38% 4% 18% 23%John Melendez* (D) 4%, Other 2%, Undecided 17%. *Withdrawn.UC BerkeleyUC Berkeley April 16–22, 2018 1,738 ± 3.5% 10% – – – 11% 28% – – 49%Other Republicans 8%, Other non-Republicans 6%, Undecided 35%Public Policy Institute of CaliforniaPublic Policy Institute of California March 4–13, 2018 1,706 ± 3.4% – – – – 16% 42% – – 41%Other with 2, Undecided with 39%Public Policy Institute of CaliforniaPublic Policy Institute of California January 21–30, 2018 1,705 ± 3.2% – – – – 17% 46% – – 36%Other with 3%, Undecided with 33%UC BerkeleyUC Berkeley December 7–16, 2017 672 ± 3.8% – – – – 27% 41% – – 32%Other/Undecided with 32%Public Policy Institute of CaliforniaPublic Policy Institute of California November 10–19, 2017 1,070 ± 4.3% – – – – 21% 45% – – 34%Other with 1%, Undecided with 33%Sextant Strategies & ResearchSextant Strategies & Research September 2017 1,197 ± 3.4% – – – – 15% 38% – – 46%Not voting with 29%, Undecided with 17%

with Timothy Charles Kalemkarian, Caren Lancona, John Melendez, and Stephen Schrader Poll source Date(s)administered Samplesize Marginof error Kevinde León(D) DianneFeinstein(D) TimothyCharlesKalemkarian(R) CarenLancona(R) PatrickLittle(R) JohnMelendez(D) StephenSchrader(R) Other /UndecidedSurveyUSASurveyUSA March 22–25, 2018 517 ± 5.0% 5% 31% 5% 2% 5% 5% 7% 42%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%SurveyUSASurveyUSA January 7–9, 2018 506 ± 4.4% 4% 34% 6% 5% 5% 2% 5% 38%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%

with Tom Steyer Pollsource Date(s)administered Samplesize Marginof error Kevinde León(D) DianneFeinstein(D) TimothyCharlesKalemkarian(R) CarenLancona(R) PatrickLittle(R) TomSteyer(D) Other /UndecidedSurveyUSA January–9, 2018 506 ± 4.4% 3% 29% 5% 5% 5% 5% 46%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%

with John Cox Pollsource Date(s)administered Samplesize Marginof error JohnCox (R) Kevinde León (D) DianneFeinstein (D) UndecidedSextant Strategies & ResearchSextant Strategies & Research September 2017 1,197 ± 3.4% 32% 14% 40% 14%

with Xavier Becerra, Kevin Faulconer, Brad Sherman, Eric Swalwell, and Ashley Swearingin Poll source Date(s)administered Samplesize Marginof error XavierBecerra (D) Kevinde León (D) KevinFaulconer (R) BradSherman (D) EricSwalwell (D) AshleySwearingin (R) UndecidedPublic Policy PollingPublic Policy Polling January 17–18, 2017 882 ± 3.3% 21% 4% 18% 11% 5% 13% 28%

Results

Democratic candidates won a combined total of 4,231,444 votes, Republican candidates 2,216,223 votes, and other candidates 223,053 votes.

General election Debates Complete video of debate, October 17, 2018

Endorsements

Fundraising