Vote--Background and history of voting : Electoral College

Today, 538 electors constitute the Electoral College. Each state is allocated electors equal to its number of representatives in the U.S. House of Representatives (currently a total of 435) plus its two senators (a total of 100). The District of Columbia is also allocated three electors. These numbers can change every 10 years, based on the results of the census. State laws differ on how electors are chosen. Learn more here.