When American voters go to the polls to vote for president, many
believe that they are participating in a direct election of the
president. Technically, this is not the case, due to the
existence of the electoral college, a constitutional relic of the
18th century.
The electoral college is the name given a group of "electors" who are nominated by political activists and party members within the states. On election day these electors, pledged to one or another candidate, are popularly elected. In December following the presidential vote the electors meet in their respective state capitals and cast ballots for president and vice president. To be elected, a president requires 270 electoral votes.
In recent history, the electors have never cast their ballots against the winner of the popular vote. To all intents and purposes, the electoral college vote, which for technical reasons is weighted in favor of whoever wins the popular election, increases the apparent majority of the winning candidate, and lends legitimacy to the popular choice. It is still possible, however, that in a close race or a multiparty race the electoral college might not cast 270 votes in favor of any candidate -- in that event, the House of Representatives will choose the next president.
The electoral college system was established in Article II, section I, of the U.S. Constitution. While it has been the subject of mild controversy in recent years, it is also seen as a stabilizing force in the electoral system.
How the Electoral College Works Today