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      Data: MIT Election Lab, VEST, Census Bureau
      Home/Elections/2020/US Senate/Iowa
      2020·US Senate·Iowa

      Iowa US Senate

      Winner
      REP
      Joni K Ernst
      51.8%864,997 votes
      Runner-up
      DEM
      Theresa Greenfield
      45.2%754,859 votes
      Margin
      R+6.6
      1,670,617 total votes
      3 candidates1,670,617 total votes
      CandidatePartyVotes ▼%Vote Share
      Joni K ErnstREP✓
      		REP864,99751.8%
      Theresa GreenfieldDEM
      		DEM754,85945.2%
      OtherOTH
      		OTH50,7613.0%

      Seat History

      US Senate in Iowa(Class I)

      2022
      Charles E GrassleyREP
      R+12.2
      2016
      Charles E GrassleyREP
      R+24.4
      2014
      Joni K ErnstREP
      R+8.3
      2010
      Charles E GrassleyREP
      R+31.1
      2008
      Tom HarkinDEM
      D+25.4
      2004
      Charles E GrassleyREP
      R+42.3
      2002
      Tom HarkinDEM
      D+10.4
      1998
      Charles E GrassleyREP
      R+37.9
      1996
      Tom HarkinDEM
      D+5.1
      1992
      Charles E GrassleyREP
      R+42.4
      1990
      Tom HarkinDEM
      D+9.1
      1986
      Charles E GrassleyREP
      R+32.5
      1984
      Tom HarkinDEM
      D+11.8
      1980
      Charles E GrassleyREP
      R+8.0
      View all US Senate history for Iowa →

      Candidates

      Joni K ErnstREP
      Record3W-0L
      Avg MarginR+38.0
      Career2012-2020
      US Senate / State Senate
      Full profile →
      Theresa GreenfieldDEM
      Record0W-1L
      Avg MarginR+6.6
      Career2020-2020
      US Senate
      Full profile →

      Also in Iowa, 2020

      President1 contest →US House4 contests →
      ← All 2020 US Senate races2020 overviewIowa profileAll elections