The 1920 United States Senate elections were elections for the United States Senate that coincided with the presidential election of Warren G. Harding. The 32 seats of Class 3 were contested in regular elections, and special elections were held to fill vacancies. Democrat Woodrow Wilson's unpopularity allowed Republicans to win races across the country, winning ten seats from the Democrats and providing them with an overwhelming 59-to-37 majority. The Republican landslide was so vast that Democrats lost over half of the contested seats this year and failed to win a single race outside the Southern United States. In fact, this is the most recent occasion where in every race decided by under 10 points, all voted for the same party. This showcased the sheer strength of the Republicans' performance in this election. Events of the election Since the passage of the Seventeenth Amendment in 1913, these elections were the closest in which the winning party in almost every Senate election mirrored the winning party for their state in the presidential election, with Kentucky being the only Senate race not to mirror their presidential result. No other Senate election cycle in a presidential year would come close to repeating this feat until 2016, in which the result of every Senate race mirrored the corresponding state's result in the presidential election. Coincidentally, that election cycle involved the same class of Senate seats, Class 3. This is also one of only five occasions where 10 or more Senate seats changed party in an election, with the other occasions being in 1932, 1946, 1958, and 1980.

, the 59 seats held after this election cycle remains the highest number of seats that the Republican Party has held as the result of an election cycle. This number rose to 60, the highest number of seats the Republicans have ever held, after Democrat senator Josiah O. Wolcott of Delaware accepted an offer from Republican governor William D. Denney to become Chancellor of the Delaware Court of Chancery, allowing Denney to name Republican T. Coleman du Pont to replace Wolcott, a seat du Pont held until the next election, in which both a special election was held for the remainder of the term and a regular election was held as the seat was normally up then, both of which du Pont lost narrowly to Democrat Thomas F. Bayard Jr. In addition, the 22-seat majority is the largest majority that the Republicans have achieved in any election since. Furthermore, this was the last time the Democrats won less than 10 Senate seats in a single election cycle.

Gains, losses, and holds Retirements Two Republicans and three Democrats retired instead of seeking re-election. One Democrat retired instead of seeking election to finish the unexpired term.

StateSenatorReplaced by Alabama (special) Colorado Illinois Louisiana Ohio South Dakota

Defeats Ten Democrats and one Republican sought re-election but lost in the primary or general election.

StateSenatorReplaced by Arizona Arkansas California Georgia Idaho Kentucky Maryland Nevada North Dakota Oklahoma Oregon

Post-election changes

StateSenatorReplaced by Delaware New Mexico Georgia Pennsylvania (class 1) Pennsylvania (class 1) Pennsylvania (class 3) Iowa Michigan

Change in composition

Before the elections   D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D D R Majority → R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R

Election results   D D D D D D D D D D D D D D D D D D D D D D D D D D D D R D D D D D D D D D R R R R R R R R R R Majority → R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R Key D Democratic R Republican

Race summary

Special elections during the 66th Congress

In these special elections, the winner was seated during 1920 or before March 4, 1921; ordered by election date.

State Incumbent Results Candidates Senator Party Electoral history Alabama(Class 2) B. B. Comer Democratic 1920 Interim appointee retired.New senator elected November 2, 1920.Democratic hold. Virginia(Class 2) Carter Glass Democratic 1920 Interim appointee elected November 2, 1920.

Elections leading to the 67th Congress

In these general elections, the winners were elected for the term beginning March 4, 1921; ordered by state.

All of the elections involved the Class 3 seats.

State Incumbent Results Candidates Senator Party Electoral history Alabama Oscar Underwood Democratic 1914 Incumbent re-elected. Arizona Marcus A. Smith Democratic 1912 1914 Incumbent lost re-election.Republican gain. Arkansas William F. Kirby Democratic 1916 Incumbent lost renomination.Democratic hold. California James D. Phelan Democratic 1914 Incumbent lost re-election.Republican gain. Colorado Charles S. Thomas Democratic 1913 1914 Incumbent lost re-election as a Nationalist.Republican gain. Connecticut Frank B. Brandegee Republican 1905 19091914 Incumbent re-elected. Florida Duncan U. Fletcher Democratic 1909 1909 1914 Incumbent re-elected. Georgia Hoke Smith Democratic 1911 1914 Incumbent lost renomination.Democratic hold. Idaho John F. Nugent Democratic 1918 1918 Incumbent lost re-election.Republican gain.Incumbent resigned January 14, 1921 to give successor preferential seniority.Winner appointed January 15, 1921. Illinois Lawrence Y. Sherman Republican 1913 1914 Incumbent retired.Republican hold. Indiana James E. Watson Republican 1916 Incumbent re-elected. Iowa Albert B. Cummins Republican 1908 1914 Incumbent re-elected. Kansas Charles Curtis Republican 1907 19071913 1914 Incumbent re-elected. Kentucky J. C. W. Beckham Democratic 1914 Incumbent lost re-election.Republican gain. Louisiana Edward J. Gay Democratic 1918 Incumbent retired.Democratic hold. Maryland John W. Smith Democratic 1908 19081914 Incumbent lost re-election.Republican gain. Missouri Selden P. Spencer Republican 1918 Incumbent re-elected. Nevada Charles Henderson Democratic 1918 1918 Incumbent lost re-election.Republican gain. New Hampshire George H. Moses Republican 1918 Incumbent re-elected. New York James W. Wadsworth Jr. Republican 1914 Incumbent re-elected. North Carolina Lee S. Overman Democratic 190319091914 Incumbent re-elected. North Dakota Asle Gronna Republican 1911 1914 Incumbent lost renomination.Republican hold. Ohio Warren G. Harding Republican 1914 Incumbent retired to run for U.S. President.Republican hold.Incumbent resigned January 13, 1921, having won the Presidency.Winner appointed January 14, 1921. Oklahoma Thomas Gore Democratic 1907 19091914 Incumbent lost renomination.Republican gain. Oregon George E. Chamberlain Democratic 19091914 Incumbent lost re-election.Republican gain. Pennsylvania Boies Penrose Republican 1897190319091914 Incumbent re-elected. South Carolina Ellison D. Smith Democratic 19091914 Incumbent re-elected. South Dakota Edwin S. Johnson Democratic 1914 Incumbent retired.Republican gain. Utah Reed Smoot Republican 190319091914 Incumbent re-elected. Vermont William P. Dillingham Republican 1900 190219081914 Incumbent re-elected. Washington Wesley L. Jones Republican 19091914 Incumbent re-elected. Wisconsin Irvine Lenroot Republican 1918 Incumbent re-elected.

Closest races Nine races had a margin of victory under 10%:

State Party of winner Margin Kentucky Republican (flip) 0.6% Maryland Republican (flip) 4.0% Nevada Republican (flip) 4.2% Oklahoma Republican (flip) 6.1% Wisconsin Republican 6.9% Oregon Republican (flip) 7.2% Idaho Republican (flip) 8.2% California Republican (flip) 8.3% Missouri Republican 9.2%

The tipping point state was Colorado, with a margin of 15.2%.

Alabama

Alabama (regular)

Alabama (special)

Arizona

Arkansas

California

Colorado

Connecticut

Florida

Georgia

Idaho

Illinois

Indiana

Iowa

Kansas

Kentucky

Louisiana

Maryland

Missouri

Nevada

New Hampshire

New York

North Carolina

North Dakota

Ohio

Oklahoma

Oregon

Pennsylvania

South Carolina

Democratic Primary RunoffCandidateVotes%±% Ellison D. Smith 65,880 60.7 +12.0 George Warren 42,735 39.3 +8.5

South Dakota

Utah

Vermont

Virginia (special)

Washington

Wisconsin

See also 1920 United States elections 1920 United States presidential election 1920 United States gubernatorial elections 1920 United States House of Representatives elections 66th United States Congress 67th United States Congress

Notes

References

Further reading