Twenty-second Amendment to the United States Constitution
As worded, the primary focus of the 22nd Amendment is on limiting individuals twice elected to the presidency from being elected again. Due to this, several issues could be raised regarding the amendment's meaning and application, especially in relation to the 12th Amendment, ratified in 1804, which states, "But no person constitutionally ineligible to the office of President shall be eligible to that of Vice-President of the United States". While it is clear that under the 12th Amendment the original constitutional qualifications of age, citizenship, and residency apply to both the president and vice president, it is unclear whether someone who is ineligible to be elected president could be elected vice president. Because of this apparent ambiguity, there may be a loophole in the 22nd Amendment whereby a two-term former-president could be elected vice president and then succeed to the presidency as a result of the incumbent's death, resignation, or removal from office (or even succeed to the presidency from some other stated office in the presidential line of succession).
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.)