The 1948 United States Senate elections were held concurrently with the election of Democratic President Harry S. Truman for a full term. The 32 seats of Class 2 were contested in regular elections, and one special election was held to fill a vacancy. Truman campaigned against an "obstructionist" Congress that had blocked many of his initiatives, and additionally, the U.S. economy recovered from the postwar recession of 1946–1947 by election day. Thus, Truman was rewarded with a Democratic gain of nine seats in the Senate, enough to give them control of the chamber. This was the last time until 2020 that Democrats flipped a chamber of Congress in a presidential election cycle.
The 1912–13 United States Senate elections were held on various dates in various states. They were the last U.S. Senate elections before the ratification of the Seventeenth Amendment in 1913, establishing direct elections for all Senate seats. Senators had been primarily chosen by state legislatures. Senators were elected over a wide range of time throughout 1912 and 1913, and a seat may have been filled months late or remained vacant due to legislative deadlock. Some states elected their senators directly even before passage of Seventeenth Amendment. Oregon pioneered direct election and experimented with different measures over several years until it succeeded in 1907. Soon after, Nebraska followed suit and laid the foundation for other states to adopt measures reflecting the people's will. By 1912, as many as 29 states elected senators either as nominees of their party's primary or in conjunction with a general election.
The 1996 United States Senate election in Illinois took place on November 5, 1996. Incumbent Democratic U.S. Senator Paul Simon chose to retire rather than seek a third term in office. In the Democratic primary, U.S. Representative Dick Durbin emerged victorious, while state representative Al Salvi won the Republican primary. Though the election was initially anticipated to be close, Durbin ended up defeating Salvi by a comfortable double-digit margin of victory, allowing him to win what would be the first of several terms in the Senate.
The 1966 United States Senate election in Illinois took place on November 8, 1966. Incumbent Democratic United States Senator Paul Douglas, seeking a fourth term in the United States Senate, faced off against Republican Charles H. Percy, a businessman and the 1964 Republican nominee for Governor of Illinois. A competitive election ensued, featuring campaign appearances by former vice president Richard M. Nixon on behalf of Percy. Ultimately, Percy ended up defeating Senator Douglas by a fairly wide margin, allowing him to win what would be the first of three terms in the Senate.
The 1986 United States Senate election in Illinois was held on November 4, 1986. The incumbent Democrat U.S. Senator Alan J. Dixon won re-election to a second term. Until 2022, this was the most recent election in which an incumbent Senator won re-election to Illinois' Class 3 seat and was elected to more than one full term.
The 1936 United States Senate election in New Hampshire took place on November 3, 1936. Incumbent Republican Senator Henry W. Keyes did not run for re-election.
The 1932 United States Senate election in Illinois took place on November 8, 1932. Incumbent Republican Otis F. Glenn was unseated by Democrat William H. Dieterich.
The 1926 United States Senate election in Illinois took place on November 2, 1926.
The 1938 United States Senate election in Illinois took place on November 8, 1938. Incumbent first-term Democrat William H. Dieterich retired. Fellow Democrat Scott W. Lucas was elected to succeed him.
The 1940 United States Senate special election in Illinois took place on November 5, 1940. The election was triggered by the vacancy left by the death in office of Democrat J. Hamilton Lewis. After Lewis' death, James M. Slattery was appointed to fill the seat in the interim period until the individual elected in the special election would be sworn-in. Slattery was the Democratic Party's nominee in the special election. He was defeated by Republican nominee Charles W. Brooks. Brooks' father-in-law, Senator John Thomas of Idaho also won a special election that same day and the two would serve in the Senate together until Thomas' death in 1945.
Two United States Senate elections were held in Illinois on March 26, 1913. The two elections were interconnected through a compromise made to elect a Democrat in the regular election and a Republican in the special election.
The 1914 United States Senate election in Illinois took place on November 3, 1914.
The 1918 United States Senate election in Illinois took place on November 5, 1918.
The 1924 United States Senate election in Illinois took place on November 4, 1924.
The 1930 United States Senate election in Illinois took place on November 4, 1930.
The United States Senate election in Illinois of 1954 took place on November 2, 1954. Incumbent Democratic United States Senator Paul Douglas was reelected to a second term.
The 1960 United States Senate election in Illinois took place on November 8, 1960. Incumbent Democratic United States Senator Paul Douglas was reelected to a third term.
The 1932 United States presidential election in Illinois took place on November 8, 1932, as part of the 1932 United States presidential election. State voters chose 29 representatives, or electors, to the Electoral College, who voted for president and vice president.
Elections were held in Illinois on Tuesday, November 5, 1940.
Elections were held in Illinois on Tuesday, November 3, 1936.
