List of United States Senators from Iowa

Iowa was admitted to the Union on December 28, 1846. Its current Senators are Republicans Charles Grassley, who has served since 1981, and Joni Ernst, who has served since 2015.

Class 2

Class 1 U.S. Senators belong to the electoral cycle that were elected for two U.S. Congresses in the first elections of 1848, and then the seat was contested every three Congresses (six years) thereafter. The seat in recent years have been contested in 1996, 2002, 2008, and 2014. The next election will be in 2020.

Class 3

Class 3 U.S. Senators belong to the electoral cycle that were elected for one United States Congress in the first elections of 1848, and then the seat was contested every three Congresses (six years) thereafter. The seat in recent years have been contested in 1998, 2004, and 2010, and 2016. The next election will be in 2022.

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