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.
United States House of Representatives
Under the Twelfth Amendment, the House has the power to elect the President if no presidential candidate receives a majority of votes in the Electoral College. The Twelfth Amendment requires the House to choose from the three candidates with the highest numbers of electoral votes. The Constitution provides that "the votes shall be taken by states, the representation from each state having one vote." It is rare for no presidential candidate to receive a majority of electoral votes. In the history of the United States, the House has only had to choose a President twice. In 1800, which was before the adoption of the Twelfth Amendment, it elected Thomas Jefferson over Aaron Burr. In 1824, it elected John Quincy Adams over Andrew Jackson and William H. Crawford. (If no vice-presidential candidate receives a majority of the electoral votes, the Senate elects the Vice President from the two candidates with the highest numbers of electoral votes.)