The 1990 United States Senate elections were held on November 6, 1990, with the 33 seats of Class 2 contested in regular elections. Special elections were also held to fill vacancies. The Democratic Party increased its majority with a net gain of one seat from the Republican Party. The election cycle took place in the middle of President George H. W. Bush's term, and as with most other midterm elections, the party not holding the presidency gained seats in Congress. This was the first time since 1980 where any party successfully defended all their own seats, and the first time where Democrats did so since 1958. It was also the last time where the Democrats (or any party) made net gains in three or more election cycles in a row, having last experienced net losses in the Senate in 1980.

These elections, along with 2022, featured the smallest seat change in history since the passage of the Seventeenth Amendment in 1913, with only one seat changing parties. This election featured Democrat Paul Wellstone defeating incumbent Republican Rudy Boschwitz in Minnesota. To date, this is the last cycle in which Democratic candidates won U.S. Senate elections in Oklahoma and Tennessee.

Background The election was held as part of the midterm election cycle of Republican President George H. W. Bush's term. Historically, the President's party struggles during the midterms.

Results summary + ↓ 56 44 Democratic Republican

Parties Total Democratic Republican Libertarian Independent OtherLast elections (1988)Before these elections 55 45 0 0 0 100Not up 38 27 — — — 65Up 17 18 — — — 35 16 17 — — — 33 1 — — — — 1 — 1 — — — 1Incumbent retired 0 3 — — — 3 0 3 — — — 3 0 0 — — — 0 Result 0 3 — — — 3Incumbent ran 17 15 — — — 32 17 14 — — — 31 1 Republican replaced by 1 Democrat — — — 1 0 0 — — — 0 Result 18 14 — — — 32Total elected 18 17 — — — 35Net gain/loss 1 1 1Nationwide vote 17,907,544 16,494,624 142,003 222,534 260,665 35,027,370 Share 51.12% 47.09% 0.41% 0.64% 0.74% 100%Result 56 44 0 0 0 100

Source: Clerk of the United States House of Representatives

Gains, losses, and holds Retirements Three Republicans retired instead of seeking re-election.

StateSenator Age at end of term AssumedofficeReplaced by Colorado 53 1979 Idaho 66 1973 New Hampshire 50 1979

Defeats Despite several candidates being in danger of losing their reelection bid, Minnesota Republican Senator Rudy Boschwitz was the only incumbent who ran for re-election to be defeated.

StateSenatorAssumedofficeReplaced by Minnesota 1978

Change in composition D Democratic R Republican

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 D D D Majority → D R R R R R D D D D 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

Result of 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 D D D Majority → D R R R R D D D D D 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

Complete list of races

Special elections In these special elections, the winners were elected in 1990.

Elections are sorted by date, then state and class.

State Incumbent Result Candidates Senator Party Electoral history Hawaii(Class 1) Democratic 1990 Interim appointee elected November 6, 1990. Indiana(Class 3) Republican 1989 Interim appointee elected November 6, 1990.

Elections leading to the next Congress In these general elections, the winners were elected for the term beginning January 3, 1991; ordered by state.

All of the elections involved the Class 2 seats.

State Incumbent Result Candidates Senator Party Electoral history Alabama Democratic 19781984 Incumbent re-elected. Alaska Republican 1968 1970197219781984 Incumbent re-elected. Arkansas Democratic 19781984 Incumbent re-elected. Colorado Republican 19781984 Incumbent retired.Republican hold. Delaware Democratic 197219781984 Incumbent re-elected. Georgia Democratic 1972 197219781984 Incumbent re-elected. Idaho Republican 197219781984 Incumbent retired.Republican hold. Illinois Democratic 1984 Incumbent re-elected. Iowa Democratic 1984 Incumbent re-elected. Kansas Republican 19781978 1984 Incumbent re-elected. Kentucky Republican 1984 Incumbent re-elected. Louisiana Democratic 1972 197219781984 Incumbent re-elected. Maine Republican 19781984 Incumbent re-elected. Massachusetts Democratic 1984 Incumbent re-elected. Michigan Democratic 19781984 Incumbent re-elected. Minnesota Republican 19781978 1984 Incumbent lost re-election.DFL gain. Mississippi Republican 19781978 1984 Incumbent re-elected. Montana Democratic 19781978 1984 Incumbent re-elected. Nebraska Democratic 19781984 Incumbent re-elected. New Hampshire Republican 19781984 Incumbent retired.Republican hold.Incumbent resigned December 4, 1990 to take a seat in the New Hampshire Senate.Winner appointed December 7, 1990. New Jersey Democratic 19781984 Incumbent re-elected. New Mexico Republican 197219781984 Incumbent re-elected. North Carolina Republican 197219781984 Incumbent re-elected. Oklahoma Democratic 19781984 Incumbent re-elected. Oregon Republican 1966197219781984 Incumbent re-elected. Rhode Island Democratic 19601966197219781984 Incumbent re-elected. South Carolina Republican 1954 (write-in)1954 1956 1956 19601966197219781984 Incumbent re-elected. South Dakota Republican 19781984 Incumbent re-elected. Tennessee Democratic 1984 Incumbent re-elected. Texas Republican 1984 Incumbent re-elected. Virginia Republican 19781979 1984 Incumbent re-elected. West Virginia Democratic 1984 Incumbent re-elected. Wyoming Republican 19781979 1984 Incumbent re-elected.

Closest races

In eight races the margin of victory was under 10%.

State Party of winner Margin Minnesota Democratic (flip) 2.63% New Jersey Democratic 3.04% Kentucky Republican 4.38% North Carolina Republican 5.19% South Dakota Republican 7.32% Oregon Republican 7.49% Iowa Democratic 9.05% Hawaii (special) Democratic 9.37%

Michigan was the tipping point state with a margin of 16.3%.

Alabama

Incumbent Democrat Howell Heflin won re-election to a third term over Republican Bill Cabaniss, State Senator and former State Representative. This was the last time the Democrats have won the Class 2 Senate Seat from Alabama until Doug Jones won the seat in 2017.

Alaska

Incumbent Republican United States Senator Ted Stevens sought re-election to a fifth term in the United States Senate, which he won easily, besting his opponents in a landslide.

Arkansas

Incumbent Democrat David Pryor won re-election uncontested.

Colorado

Incumbent Republican senator William L. Armstrong did not seek re-election to another term. Republican congressman Hank Brown won the open seat, defeating Democratic nominee Josie Heath, former Boulder County Commissioner

Delaware

Incumbent Democratic Joe Biden won re-election to a fourth term, defeating Republican challenger Deputy Attorney General of Delaware M. Jane Brady. Brady decided to run because she felt that Biden's liberal voting record did not reflect the political positions of Delawareans. The election had a turnout rate of under 40% of registered voters. Biden won in a landslide with over 60% of the vote improving on his 1984 margin, winning all three counties and all 41 state house districts.

Georgia

Incumbent Democrat Sam Nunn won re-election to a fourth term uncontested.

Hawaii (special)

Incumbent Democrat Daniel Akaka was elected to finish the term ending in 1995 over Republican U.S. Representative Pat Saiki. Akaka had been appointed by Governor John Waihee in April 1990 to fill the vacancy created by the death of Spark Matsunaga.

Idaho

Republican Rep. Larry Craig defeated Democratic former state legislator Ron Twilegar for the seat of U.S. Senator Jim McClure, who did not seek re-election.

Illinois

Incumbent Democrat Paul Simon sought re-election to the United States Senate. Simon was opposed by Republican nominee Lynn Morley Martin, a United States Congresswoman from Illinois's 16th congressional district, whom he easily defeated to win a second and final term in the Senate.

Indiana (special)

Incumbent Republican Dan Coats, who was recently appointed to this seat two years prior, won election to serve out the remainder of the term, beating Democratic State Representative Baron Hill.

During the 1988 presidential election, Republican nominee Vice President George H. W. Bush selected U.S. Senator Dan Quayle of Indiana as his vice presidential nominee. The Bush-Quayle ticket defeated the Dukakis–Bentsen ticket in the general election by a 53%-46% margin, capturing 40 states and 426 electoral votes.

In preparation for the pending vacancy, Governor Robert D. Orr appointed four-term U.S. Representative Dan Coats to fill Quayle's seat on December 12, 1988. Coats was a former aide to Quayle, whom he had succeeded as U.S. Representative for Indiana's 4th congressional district in 1981. Quayle eventually resigned his Senate seat on January 3, 1989, and Coats was immediately sworn into office.

Coats used television commercials that raised questions about Hill's consistency in opposing new taxes, and Hill gained notoriety for walking the length of the state to meet voters.

Iowa

Incumbent Democrat Tom Harkin sought re-election to a second term in the United States Senate. Harkin was opposed by Republican United States Congressman Tom Tauke, from Iowa's 2nd congressional district, and both Harkin and Tauke won their primaries uncontested. Though Harkin performed slightly worse than he had six years earlier, he was successful in his re-election bid and defeated Tauke.

Kansas

Incumbent Republican Nancy Kassebaum won re-election to her third full term, over Democrat Dick Williams, an educator at Wichita State University

Kentucky

Incumbent Republican Mitch McConnell won re-election to a second term over Democrat Harvey Sloane, former Mayor of Louisville

Louisiana

Incumbent Democrat J. Bennett Johnston Jr. won re-election to a fourth term and avoided a runoff, beating Republican David Duke, State Representative and former Grand Wizard of the Ku Klux Klan.

This election was viewed at the onset as potentially competitive, as Senator Johnston was viewed as vulnerable in light of Louisiana's economic troubles at the time and Senator Johnston's voting record viewed by Republicans as too liberal. The Republican Party leadership endorsed the candidacy of State Senator Ben Bagert, who was picked over Secretary of State Fox McKeithen, State Representative Quentin Dastugue and State Representative David Duke. David Duke, however, continued his candidacy and slowly overtook Bagert in attention and in the polls. Duke attracted national attention to the race with his involvement with white supremacist groups and his appeals to white resentment over affirmative-action programs. With Bagert failing to gain traction, the National Republican Senatorial Committee tried to recruit former Governor David Treen to jump into the race. When Treen passed, the effort turned from supporting Bagert to stopping Duke.