Twenty-second Amendment to the United States Constitution
The amendment prohibits any individual who has been elected president twice from being elected again. Under the amendment, an individual who fills an unexpired presidential term lasting greater than two years is also prohibited from winning election as president more than once. Scholars debate whether the amendment prohibits affected individuals from succeeding to the presidency under any circumstances or whether it only applies to presidential elections.
Lame duck (politics)
The term "lame duck president" traditionally is reserved for a president who is serving out the remainder of their term after having been defeated for re-election. In this sense, the following presidents, since the twentieth century, have been lame ducks: William Howard Taft, who was defeated for re-election in 1912; Herbert Hoover, who was defeated for re-election in 1932; Gerald R. Ford, who was defeated in 1976; Jimmy Carter, who was defeated for re-election in 1980; and George H. W. Bush, who was defeated for re-election in 1992. To date, he is the last sitting president to lose in a re-election bid.