US presidential election

The election of President and Vice President of the United States is an indirect election in which citizens of the United States who are registered to vote in one of the 50 U.S. states or Washington, D.C. cast ballots for members of the U.S. Electoral College, known as electors. These electors then in turn cast direct votes, known as electoral votes, for President and Vice President. The candidate who receives an absolute majority of electoral votes for President or Vice President (currently, at least 270 out of a total of 538) is then elected to that office. If no candidate receives an absolute majority for President, the House of Representatives chooses the President; if no one receives a majority for Vice President, then the Senate chooses the Vice President.

The Electoral College and its procedure is established in the U.S. Constitution by Article II, Section 1, Clauses 2 and 4; and the Twelfth Amendment (which replaced Clause 3 after its ratification in 1804). Under Clause 2, each of the states casts as many electoral votes as the total number of its Senators and Representatives in Congress, while, per the Twenty-third Amendment ratified in 1961, Washington, D.C. casts the same number of electoral votes as the least-represented state, which is three. Also under Clause 2, the manner for choosing electors is determined by each state legislature, not directly by the federal government. Many state legislatures previously selected their electors directly, but over time all of them switched to using the popular vote to help determine electors, which persists today. Once chosen, electors generally cast their electoral votes for the candidate who won the plurality in their state, but at least 21 states do not have provisions that specifically address this behavior; those who vote in opposition to the plurality are known as "faithless" or "unpledged electors". In modern times, faithless and unpledged electors have not affected the ultimate outcome of an election, so the results can generally be determined based on the state-by-state popular vote.

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