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      Akashic HQ provides deep political data analysis covering 165 years of U.S. elections.

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      Data: MIT Election Lab, VEST, Census Bureau
      Home/Elections/1966/US Senate/Illinois
      1966·US Senate·Illinois

      Illinois US Senate

      Winner
      REP
      Charles H. Percy
      55.0%2,100,449 votes
      Runner-up
      DEM
      Paul H. Douglas
      43.9%1,678,147 votes
      Margin
      R+11.1
      3,822,725 total votes
      3 candidates3,822,725 total votes
      CandidatePartyVotes ▼%Vote Share
      Charles H. PercyREP✓
      		REP2,100,44955.0%
      Paul H. DouglasDEM
      		DEM1,678,14743.9%
      OtherOTH
      		OTH44,1291.1%

      Seat History

      US Senate in Illinois(Class I)

      2022
      Tammy DuckworthDEM
      D+15.3
      2020
      Richard J DurbinDEM
      D+16.1
      2016
      Tammy DuckworthDEM
      D+15.1
      2014
      Richard J DurbinDEM
      D+10.8
      2010
      Mark Steven KirkREP
      R+1.6
      2008
      Richard J DurbinDEM
      D+39.3
      2004
      Barack ObamaDEM
      D+42.9
      2002
      Richard J DurbinDEM
      D+22.3
      1998
      Peter G FitzgeraldREP
      R+2.9
      1996
      Richard J DurbinDEM
      D+15.4
      1992
      Carol Moseley-BraunDEM
      D+10.2
      1990
      Paul SimonDEM
      D+30.1
      1986
      Alan J. DixonDEM
      D+31.4
      1984
      Paul SimonDEM
      D+1.9
      1980
      Alan J. DixonDEM
      D+13.5
      View all US Senate history for Illinois →

      Candidates

      Charles H. PercyREP
      Record3W-2L
      Avg MarginR+7.6
      Career1964-1984
      US Senate / Governor
      Full profile →
      Paul H. DouglasDEM
      Record3W-1L
      Avg MarginD+4.0
      Career1948-1966
      US Senate
      Full profile →
      ← All 1966 US Senate races1966 overviewIllinois profileAll elections