Why does the party that holds the presidency often loses seats in the off-year elections?

Last Updated

October 29, 2018

Notes

Beginning with Obama, job approval is the average job approval during the noted half month period.
Seats held by Progressives or Independents are attributed to the major party with which they caucused.
• A "lame-duck" mid-term (Congressional) election is one that occurs when the incumbent President is constitutionally prohibited from seeking re-election in the next scheduled presidential election. Arguable exceptions are noted below.
* Harry S. Truman was not prevented from running for a 3rd term in 1952 although he chose not to seek re-election.
† Lyndon B. Johnson was not a lame-duck president in 1966, but in March 1968 he chose not to seek
re-election.
± Although Gerald Ford was not a lame-duck president and did run for re-election in 1976, the 1974 mid-term election took place only three months after the resignation of Richard Nixon and only two months following Ford's pardon of Nixon.

Source(s)

Presidential job approval data from The Gallup Poll.
• 1950 — 1994 Congressional seat gain/loss from Lyn Ragsdale, Vital Statistics on the Presidency, Washington, DC: CQ Press, 1998.
• 1934 — 1946 & 1998 — 2018 Congressional seat gain/loss;  all years Senate seats to defend, by The American Presidency Project

Citations

The American Presidency Project. "Seats in Congress Gained/Lost by the President's Party in Mid-Term Elections." Santa Barbara, CA: University of California. Available from the World Wide Web: https://www.presidency.ucsb.edu/node/332343/.

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