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      Data: MIT Election Lab, VEST, Census Bureau
      Home/Elections/2018/US House/California/CA-21
      2018·US House·California·District profile →

      California District 21 US House

      Winner
      DEM
      Tj Cox
      50.4%57,239 votes
      Runner-up
      REP
      David G Valadao
      49.6%56,377 votes
      Margin
      D+0.8
      113,616 total votes
      2 candidates113,616 total votes
      CandidatePartyVotes ▼%Vote Share
      Tj CoxDEM✓
      		DEM57,23950.4%
      David G ValadaoREP
      		REP56,37749.6%

      Presidential Vote by District

      5 elections · 2008–2024 · 118th Congress boundaries
      Latest (2024)D+3.8
      Shift vs 2020↓ R+16.5
      R+20EvenD+2020082012201620202024
      YearDem %Rep %MarginTurnout
      202450.6%46.8%D+3.8200,149
      202059.1%38.8%D+20.3226,362
      201658.2%36.5%D+21.8172,953
      201259.4%40.6%D+18.7152,341
      200857.8%41.4%D+16.4155,724

      Seat History

      US House in California

      2024
      Jim CostaDEM
      D+5.2
      2022
      Jim CostaDEM
      D+8.4
      Redistricted
      2020
      David G ValadaoREP
      R+0.9
      2016
      David G ValadaoREP
      R+13.5
      2014
      David G ValadaoREP
      R+15.7
      2012
      David G ValadaoREP
      R+15.5
      Redistricted
      2010
      Devin G NunesREP
      R+100.0
      2008
      Devin G NunesREP
      R+36.8
      2006
      Devin G NunesREP
      R+36.8
      2004
      Devin G NunesREP
      R+46.3
      2002
      Devin G NunesREP
      R+44.3
      Redistricted
      2000
      William M ThomasREP
      R+46.8
      1998
      William M ThomasREP
      R+78.9
      1996
      William M ThomasREP
      R+39.4
      View all US House history for California →

      Candidates

      Tj CoxDEM
      Record1W-2L
      Avg Margin---
      Career2006-2020
      US House
      Full profile →
      David G ValadaoREP
      Record7W-1L
      Avg MarginR+21.1
      Career2010-2024
      US House / State House
      Full profile →

      Also in California, 2018

      US Senate1 contest →Governor1 contest →
      ← All 2018 US House races2018 overviewCalifornia profileAll elections