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      Data: MIT Election Lab, VEST, Census Bureau
      Home/Elections/1990/US House/California/CA-20
      1990·US House·California·District profile →

      California District 20 US House

      Winner
      REP
      William M Thomas
      59.8%112,962 votes
      Runner-up
      DEM
      Michael A Thomas
      34.5%65,101 votes
      Margin
      R+25.3
      188,925 total votes
      4 candidates188,925 total votes
      CandidatePartyVotes ▼%Vote Share
      William M ThomasREP✓
      		REP112,96259.8%
      Michael A ThomasDEM
      		DEM65,10134.5%
      William H DilbeckLIB
      		LIB10,5555.6%
      WriteinOTH
      		OTH3070.2%

      Presidential Vote by District

      5 elections · 2008–2024 · 118th Congress boundaries
      Latest (2024)R+30.3
      Shift vs 2020↓ R+5.5
      R+20EvenD+2020082012201620202024
      YearDem %Rep %MarginTurnout
      202433.7%64.0%R+30.3328,446
      202036.4%61.3%R+24.9349,862
      201631.8%62.6%R+30.8270,759
      201233.0%67.0%R+33.9246,703
      200834.5%64.9%R+30.4254,364

      Seat History

      US House in California

      2024
      Vince FongREP
      R+100.0
      2022
      Kevin McCarthyREP
      R+34.5
      Redistricted
      2020
      Jimmy PanettaDEM
      D+53.5
      2018
      Jimmy PanettaDEM
      D+81.4
      2016
      Jimmy PanettaDEM
      D+41.5
      2014
      Sam FarrDEM
      D+75.2
      2012
      Sam FarrDEM
      D+48.1
      Redistricted
      2010
      Jim CostaDEM
      D+3.4
      2008
      Jim CostaDEM
      D+48.7
      2006
      Jim CostaDEM
      D+100.0
      2004
      Jim CostaDEM
      D+6.8
      2002
      Calvin M DooleyDEM
      D+29.4
      Redistricted
      2000
      Calvin M DooleyDEM
      D+6.8
      1998
      Calvin M DooleyDEM
      D+21.5
      1996
      Calvin M DooleyDEM
      D+17.4
      View all US House history for California →

      Candidates

      WriteinOTH
      Record0W-2660L
      Avg Margin---
      Career1976-2024
      US House / Governor
      Full profile →
      William M ThomasREP
      Record16W-0L
      Avg MarginR+11.8
      Career1974-2004
      US House / State House
      Full profile →
      Michael A ThomasREP
      Record0W-2L
      Avg MarginD+33.6
      Career1990-2018
      State House / US House
      Full profile →
      William H DilbeckLIB
      Record0W-2L
      Avg Margin---
      Career1990-1992
      US House
      Full profile →

      Also in California, 1990

      Governor1 contest →
      ← All 1990 US House races1990 overviewCalifornia profileAll elections