The 1958 United States Senate elections were elections for the United States Senate which occurred in the middle of President Dwight D. Eisenhower's second term. Thirty-two seats of Class 1 were contested in regular elections, the new state of Alaska held its first Senate elections for its Class 2 and 3 seats, and two special elections were held to fill vacancies.

As is common in midterm elections, the party in the White House lost seats, but losses this year were heavy due to the Recession of 1958, the Eisenhower Administration's position on right-to-work issues that galvanized the labor unions which supported Democrats, and the launch of Sputnik. This was the first time since 1934 that Democrats gained seats in this class of Senators. Democrats won both seats in West Virginia, marking the last time Democrats would simultaneously flip both of a state's Senate seats until Georgia's elections in 2020 and 2021.

The Democratic Party gained a record 15 seats in this election, defeating 10 Republican incumbents, gaining three open Republican seats, and winning both seats from the new state of Alaska. This gave the Democrats a strong Senate majority of 64–34 over the Republicans, and the largest swing in the history of the Senate. After the new state of Hawaii elected its first Senators in 1959, the Senate's balance changed to 65–35.

This is only one of two occasions in U.S. history that 10 or more Senate seats changed hands in a mid-term election (the other being in 1946), and also one of five occasions where 10 or more Senate seats changed hands in an election, with the other occasions being in 1920, 1932, 1946, and 1980.

Results summary + ↓ 64 34 Democratic Republican

For the November 5 and 25, 1958 regular and special elections.

Colored shading indicates party with largest share of that row. Parties Total Democratic Republican Other Last elections (1956)Before these elections 49 47 0 96 Not up 36 26 0 62 19 11 0 30 17 15 0 32 Up 13 21 — 34 12 20 — 32 1 1 — 2 Incumbent retired 0 6 — 6 0 3 — 3 3 Republicans replaced by 3 Democrats — 3 Result 3 3 0 6 Incumbent ran 13 15 — 28 13 5 — 18 10 Republicans replaced by 10 Democrats — 10 0 0 — 0 Result 23 5 0 28 New state 2 0 0 2 Total elected 28 8 0 36 Net gain/loss 15 13 15 Nationwide vote 21,426,124 16,622,338 678,147 38,726,609 Share 55.33% 42.92% 1.75% 100% Result 64 34 0 98

Source: Clerk of the U.S. House of Representatives

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

StateSenatorReplaced by California Indiana New Jersey New York Pennsylvania Vermont

Defeats Ten Republicans sought re-election but lost in the general election.

StateSenatorReplaced by Connecticut Maine Michigan Minnesota Nevada Ohio Utah West Virginia (regular) West Virginia (special) Wyoming

New states Alaska was admitted into the Union and elected two Democrats to the Senate.

StateSenator Alaska (class 2) Alaska (class 3)

Post-election states Hawaii was admitted into the Union and elected one Democrat and one Republican to the Senate on July 28, 1959.

StateSenator Hawaii (class 1) Hawaii (class 3)

Post election changes Two Democrats left the Senate after the election. Both seats were filled by Democrats.

StateSenatorReplaced by Oregon Missouri

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 D D Majority ↑ TBD R R R R R R R R TBD 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

After 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 Majority → D D D D D D D D D D 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

Key: D Democratic R Republican

Race summaries

Special / new state elections In the special elections, the winners were seated during 1958 or before January 3, 1959. In the new state elections, the winners were seated with the new Congress on January 3, 1959. Ordered by election date.

State Incumbent Results Candidates Senator Party Electoral history North Carolina(class 2) B. Everett Jordan Democratic 1958 Interim appointee elected November 4, 1958. West Virginia(class 2) John D. Hoblitzell Jr. Republican 1958 Interim appointee lost election.New senator elected November 4, 1958.Democratic gain. Alaska(class 2) Alaska admitted as a state January 3, 1959. New state.New senator elected November 25, 1958.Democratic gain. Alaska(class 3) New state.New senator elected November 25, 1958.Democratic gain.

Elections leading to the next Congress In these regular elections, the winners were elected for the term beginning January 3, 1959; ordered by state.

All of the elections involved the Class 1 seats.

State Incumbent Results Candidates Senator Party Electoral history Arizona Republican 1952 Incumbent re-elected. California Republican 1945 1946 1952 Incumbent retired to run for California Governor.New senator elected.Democratic gain. Connecticut Republican 1952 1952 1952 Incumbent lost re-election.New senator elected.Democratic gain. Delaware Republican 19461952 Incumbent re-elected. Florida Democratic 1946 19461952 Incumbent re-elected. Indiana Republican 1944 19461952 Incumbent retired.New senator elected.Democratic gain. Maine Republican 1952 Incumbent lost re-election.New senator elected.Democratic gain. Maryland Republican 1952 Incumbent re-elected. Massachusetts Democratic 1952 Incumbent re-elected. Michigan Republican 1952 1952 Incumbent lost re-election.New senator elected.Democratic gain. Minnesota Republican 19461952 Incumbent lost re-election.New senator elected.Democratic–Farmer–Labor gain. Mississippi Democratic 1947 1952 Incumbent re-elected. Missouri Democratic 1952 Incumbent re-elected. Montana Democratic 1952 Incumbent re-elected. Nebraska Republican 1954 Incumbent re-elected. Nevada Republican 19461952 Incumbent lost re-election.New senator elected.Democratic gain. New Jersey Republican 1944 19461952 Incumbent retired.New senator elected.Democratic gain. New Mexico Democratic 1935 1936 194019461952 Incumbent re-elected. New York Republican 19461952 Incumbent retired.New senator elected.Republican hold. North Dakota Republican 194019461952 Incumbent re-elected. Ohio Republican 19461952 Incumbent lost re-election.New senator elected.Democratic gain. Pennsylvania Republican 19461952 Incumbent retired.New senator elected.Republican hold. Rhode Island Democratic 1950 1952 Incumbent re-elected. Tennessee Democratic 1952 Incumbent re-elected. Texas Democratic 1957 Incumbent re-elected. Utah Republican 19461952 Incumbent lost re-election.New senator elected.Democratic gain. Vermont Republican 1946 1946 1952 Incumbent retired.New senator elected.Republican hold. Virginia Democratic 1933 1933 1934194019461952 Incumbent re-elected. Washington Democratic 1952 Incumbent re-elected. West Virginia Republican 19421948 1956 Incumbent lost re-election.New senator elected.Democratic gain. Wisconsin Democratic 1957 Incumbent re-elected. Wyoming Republican 1952 Incumbent lost re-election.New senator elected.Democratic gain.

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

State Party of winner Margin Wyoming Democratic (flip) 1.6% Maryland Republican 2.0% New York Republican 2.4% Utah Democratic (flip) 3.9% Vermont Republican 4.4% New Jersey Democratic (flip) 4.5% Ohio Democratic (flip) 5.0% Alaska (class 3) Democratic (flip) 5.2% Minnesota Democratic (flip) 6.3% Delaware Republican 6.6% Michigan Democratic (flip) 7.5%

Maine was the tipping point state with a margin of 21.6%.

Alaska

Alaska would become a new state January 3, 1959, and it elected two initial senators November 25, 1958, in advance of statehood. The Democratic Party thereby picked up 2 more seats.

In their next elections, Alaska's senators would be elected to 6-year terms.

The class 2 race, for the 2-year term ending in 1961, was between the Democratic incumbent territorial delegate Bob Bartlett, and the Republican Juneau attorney R. E. Robertson.

Bartlett would be re-elected twice and serve until his death in 1968.

The class 3 race, for the 4-year term ending in 1963, pitted two former territorial governors, Democrat Ernest Gruening against Republican Mike Stepovich. Gruening won a close race.

Gruening would be re-elected in 1962 and serve until losing renomination in 1968.

Arizona

California

Connecticut

In Connecticut, Democrat Thomas J. Dodd defeated incumbent senator William A. Purtell who ran for a second term.

Delaware

Two-term Republican John J. Williams was re-elected to a third term.

Williams would be re-elected in 1964, serving four terms until his 1970 retirement.

Florida

Incumbent Democrat Senator Holland, a conservative, was challenged by former senator Claude Pepper, who had been unseated in 1950. Holland had played a role in recruiting George A. Smathers to run against the liberal Pepper in that election. The two served as colleagues in the Senate from 1947 to 1951.

Indiana

Incumbent Republican William E. Jenner did not seek a second full term in office and was replaced by Democrat Vance Hartke, the mayor of Evansville. Hartke defeated incumbent Republican Governor of Indiana Harold W. Handley.

Jenner resigned shortly before the election and urged Handley, Jenner's political protégé, to seek his seat. A plan was proposed whereby Handley would resign the governorship, his lieutenant would appoint him senator, and he would finish the term and run as an incumbent. When the plan was revealed to the party leadership, they strongly advised him to not implement it because they feared it would hurt the party and be perceived as a scandal.

Handley did not resign from the governorship during his campaign and was widely criticized for the unprecedented action. Hartke accused Handley of raising taxes, breaking of his campaign promise, his reluctance in supporting right-to-work, and rising state unemployment. Statewide unemployment was just above 10% in April, but dropped to 6.9% by the end of September.

Maine

Maine held its election September 8, 1958, in keeping with its routine practice of holding elections before the November national Election Day. Democrat Edmund Muskie defeated one-term Republican incumbent, Frederick G. Payne by a wide margin, 61–39%.

Maryland

Massachusetts

Michigan

Minnesota

In Minnesota, Democratic Representative Eugene McCarthy defeated incumbent senator Edward John Thye who ran for a third term.

Mississippi

Two-term Democrat John C. Stennis was re-elected with no opposition.

Stennis would be re-elected four more times, serving until his retirement in 1989.

Missouri

Incumbent Democrat Stuart Symington was re-elected to a second term. Hazel Palmer was the first woman ever nominated for United States senator in Missouri.

Montana

Incumbent Mike Mansfield, who was first elected to the Senate in 1952, ran for re-election. Mansfield won the Democratic primary comfortably, and moved on to the general election, where he was opposed by Lou W. Welch, a millworker and the Republican nominee. In contrast to the close campaign in 1952, Mansfield defeated Welch in a landslide and won his second term in the Senate easily.

Nebraska

Republican Roman Hruska had won a 1954 special election and ran for a full term. He beat Democratic attorney Frank B. Morrison, who had previously lost his challenger bid for Nebraska's 1st congressional district.

Hruska would be re-elected two more times and serve until his 1976 retirement.

Morrison would be elected Governor of Nebraska in 1960 and serve there for six years from 1961 to 1967, and was re-elected twice while running unsuccessfully for U.S. senator.

Nevada

In Nevada, incumbent Republican George W. Malone ran for re-election to a third term, but was defeated by Democrat Howard Cannon.