The United States Electoral College is the mechanism established by the United States Constitution for the indirect election of the President of the United States and Vice President of the United States. Citizens of the United States vote in each state at a general election to choose a slate of "electors" pledged to vote for a party's candidate.

The Twelfth Amendment requires each elector to cast one vote for president and another vote for vice president. In each state and the District of Columbia, electors are chosen every four years on the Tuesday after the first Monday in November, and then meet to cast ballots on the first Monday after the second Wednesday in December. The candidates who receive an absolute majority of electoral votes among the states are elected President and Vice President of the United States when the Electoral College vote is certified by Congress in January.

Currently, there is a total of 538 electors, there being 435 representatives and 100 senators, plus the three electors allocated to Washington, D.C. The six states with the most electors are California (55), Texas (38), New York (29), Florida (29), Illinois (20) and Pennsylvania (20). The seven smallest states by population – Alaska, Delaware, Montana, North Dakota, South Dakota, Vermont, and Wyoming – have three electors each. This is because each of these states is entitled to one representative and two senators.

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