Current delegation

John Thune (R)

Mike Rounds (R)

South Dakota was admitted to the Union on November 2, 1889, and elects U.S. senators to class 2 and class 3. Its current U.S. senators are Republicans John Thune (since 2005) and Mike Rounds (since 2015). Karl E. Mundt is South Dakota's longest-serving senator (1948–1973). South Dakota is one of fifteen states alongside Arizona, Colorado, Florida, Georgia, Hawaii, Idaho, Indiana, Louisiana, Maine, Massachusetts, Minnesota, Missouri, Nevada and Utah to have a younger senior senator and an older junior senator.

List of senators

Class 2 Class 2 U.S. senators belong to the electoral cycle that has recently been contested in 2002, 2008, 2014, and 2020. The next election will be in 2026.						C	Class 3 Class 3 U.S. senators belong to the electoral cycle that has recently been contested in 2004, 2010, 2016, and 2022. The next election will be in 2028.
#	Senator	Party	Dates in office	Electoral history	T		T	Electoral history	Dates in office	Party	Senator	#
1	Richard Pettigrew	Republican	Nov 2, 1889 – Mar 3, 1901	Elected in 1889.	1	51st	1	Elected in 1889. Lost re-election.	Nov 2, 1889 – Mar 3, 1891	Republican	Gideon C. Moody	1
						52nd	2	Elected in 1891.[1]	Mar 4, 1891 – Jul 1, 1901	Independent	James H. Kyle	2
						53rd				Populist
				Re-elected in 1894. Lost re-election.	2	54th
		Silver Republican				55th	3	Re-elected in 1897.[2] Died.
						56th
2	Robert J. Gamble	Republican	Mar 4, 1901 – Mar 3, 1913	Elected in 1901.[3]	3	57th				Republican
									Jul 1, 1901 – Jul 11, 1901	Vacant
								Appointed to continue Kyle's term. Elected in 1903 to finish Kyle's term.[4]	Jul 11, 1901 – Mar 3, 1909	Republican	Alfred B. Kittredge	3
						58th	4	Elected to a full term in 1903.[5] Lost renomination.
						59th
				Re-elected in 1907. Lost renomination.	4	60th
						61st	5	Elected in 1909. Lost renomination.	Mar 4, 1909 – Mar 3, 1915	Republican	Coe Crawford	4
						62nd
3	Thomas Sterling	Republican	Mar 4, 1913 – Mar 3, 1925	Elected in 1913.	5	63rd
						64th	6	Elected in 1914. Retired.	Mar 4, 1915 – Mar 3, 1921	Democratic	Edwin S. Johnson	5
						65th
				Re-elected in 1918. Lost renomination.	6	66th
						67th	7	Elected in 1920.	Mar 4, 1921 – Dec 20, 1936	Republican	Peter Norbeck	6
						68th
4	William McMaster	Republican	Mar 4, 1925 – Mar 3, 1931	Elected in 1924. Lost re-election.	7	69th
						70th	8	Re-elected in 1926.
						71st
5	William J. Bulow	Democratic	Mar 4, 1931 – Jan 3, 1943	Elected in 1930.	8	72nd
						73rd	9	Re-elected in 1932. Died.
						74th
									Dec 20, 1936 – Dec 29, 1936	Vacant
								Appointed to continue Norbeck's term. Lost nomination to a full term.	Dec 29, 1936 – Nov 8, 1938	Democratic	Herbert Hitchcock	7
				Re-elected in 1936. Lost renomination.	9	75th
								Elected to finish Norbeck's term. Retired.	Nov 9, 1938 – Jan 3, 1939	Republican	Gladys Pyle	8
						76th	10	Elected in 1938.	Jan 3, 1939 – Jan 3, 1951	Republican	Chan Gurney	9
						77th
6	Harlan J. Bushfield	Republican	Jan 3, 1943 – Sep 27, 1948	Elected in 1942. Died.	10	78th
						79th	11	Re-elected in 1944. Lost renomination.
						80th
Vacant			Sep 27, 1948 – Oct 6, 1948
7	Vera C. Bushfield	Republican	Oct 6, 1948 – Dec 26, 1948	Appointed to finish her husband's term. Resigned when successor appointed.
Vacant			Dec 26, 1948 – Dec 31, 1948
8	Karl Mundt	Republican	Dec 31, 1948 – Jan 3, 1973	Appointed to finish Bushfield's term, having been elected to the next term.
				Elected in 1948	11	81st
						82nd	12	Elected in 1950.	Jan 3, 1951 – Jun 22, 1962	Republican	Francis Case	10
						83rd
				Re-elected in 1954.	12	84th
						85th	13	Re-elected in 1956. Died.
						86th
				Re-elected in 1960.	13	87th
									Jun 22, 1962 – Jul 9, 1962	Vacant
								Appointed to finish Case's term. Lost election to full term.	Jul 9, 1962 – Jan 3, 1963	Republican	Joe Bottum	11
						88th	14	Elected in 1962.	Jan 3, 1963 – Jan 3, 1981	Democratic	George McGovern	12
						89th
				Re-elected in 1966. Retired.	14	90th
						91st	15	Re-elected in 1968.
						92nd
9	James Abourezk	Democratic	Jan 3, 1973 – Jan 3, 1979	Elected in 1972. Retired.	15	93rd
						94th	16	Re-elected in 1974. Lost re-election.
						95th
10	Larry Pressler	Republican	Jan 3, 1979 – Jan 3, 1997	Elected in 1978.	16	96th
						97th	17	Elected in 1980. Lost re-election.	Jan 3, 1981 – Jan 3, 1987	Republican	James Abdnor	13
						98th
				Re-elected in 1984.	17	99th
						100th	18	Elected in 1986.	Jan 3, 1987 – Jan 3, 2005	Democratic	Tom Daschle	14
						101st
				Re-elected in 1990. Lost re-election.	18	102nd
						103rd	19	Re-elected in 1992.
						104th
11	Tim Johnson	Democratic	Jan 3, 1997 – Jan 3, 2015	Elected in 1996.	19	105th
						106th	20	Re-elected in 1998. Lost re-election.
						107th
				Re-elected in 2002.	20	108th
						109th	21	Elected in 2004.	Jan 3, 2005 – present	Republican	John Thune	15
						110th
				Re-elected in 2008. Retired.	21	111th
						112th	22	Re-elected in 2010.
						113th
12	Mike Rounds	Republican	Jan 3, 2015 – present	Elected in 2014.	22	114th
						115th	23	Re-elected in 2016.
						116th
				Re-elected in 2020.	23	117th
						118th	24	Re-elected in 2022.
						119th
To be determined in the 2026 election.					24	120th
						121st	25	To be determined in the 2028 election.
#	Senator	Party	Years in office	Electoral history	T	C	T	Electoral history	Years in office	Party	Senator	#
Class 2							Class 3