United States presidential election

The United States presidential election 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 the District of Columbia cast ballots for members of the Electoral College, known as electors. These electors then in turn cast direct votes, known as electoral votes, in their respective state capitals for President and Vice President of the United States. Each of the states casts as many electoral votes as the total number of its Senators and Representatives in Congress, while Washington, D.C. casts the same number of electoral votes as the least-represented state, which is three.

Once the voting for the presidential election has concluded and all the votes for each state have been accounted for, the electors are then advised as to what candidate won the majority in their state. The electors of that state then will cast the vote of that candidate to represent the people of their region's majority decision. However, “Twenty one states do not have provisions that are fairly specific in directing the electors to vote for the presidential and vice-presidential candidates of their party.” This means that an elector could possibly vote against the majority decision of the state due to there being no law that binds electors otherwise in those states. In modern times, almost all electors vote for a particular presidential candidate that their state's majority decided upon; thus, the results of the election can generally be determined based on the state-by-state popular vote. 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 projected to be elected to that office. If no candidate receives an absolute majority of electoral votes for President, the House of Representatives chooses the President; if no candidate receives an absolute majority for Vice President, the Senate chooses the Vice President.

...
Wikipedia