The blue bars show the number of Democrats in the Senate after the election in the year given. The red bars show the numbers of Republicans. The numbers show the post-election seats for each party. The black lines show how many seats each party had prior to the election. Third party seats are not counted. The background color shows which party controlled the White House at the time of the election. Popular election of senators began in 1914.

2000s	2008 Bush	2006 Bush	2004 Bush	2002 Bush	2000 Clinton
1990s	1998 Clinton	1996 Clinton	1994 Clinton	1992 Bush	1990 Bush
1980s	1988 Reagan	1986 Reagan	1984 Reagan	1982 Reagan	1980 Carter
1970s	1978 Carter	1976 Ford	1974 Ford	1972 Nixon	1970 Nixon
1960s	1968 Johnson	1966 Johnson	1964 Johnson	1962 Kennedy	1960 Eisenhower
1950s	1958 Eisenhower	1956 Eisenhower	1954 Eisenhower	1952 Truman	1950 Truman
1940s	1948 Truman	1946 Truman	1944 Roosevelt	1942 Roosevelt	1940 Roosevelt
1930s	1938 Roosevelt	1936 Roosevelt	1934 Roosevelt	1932 Roosevelt	1930 Hoover
1920s	1928 Hoover	1926 Coolidge	1924 Coolidge	1922 Harding	1920 Harding
1910s	1918 Wilson	1916 Wilson	1914 Wilson