Did you know that in the United States, voters do not actually vote for the President, but only for the representatives who will elect the President?
The Electoral College consists of 538 popularly elected representatives who formally select the President and Vice President of the United States. In 2008, it will make this selection on December 15. The Electoral College is an example of an indirect election.
Each state has a number of electors equal to the number of its Senators and Representatives in the United States Congress. Additionally, Washington, D.C. is given a number of electors equal to the number held by the "least populous" state. U.S. territories are not represented in the Electoral College.
State Electoral Votes State Electoral Votes Alabama 9 Montana 3 Alaska 3 Nebraska 5** Arizona 10 Nevada 5 Arkansas 6 New Hampshire 4 California 55 New Jersey 15 Colorado 9 New Mexico 5 Connecticut 7 New York 31 Delaware 3 North Carolina 15 Washington, D.C. 3 North Dakota 3 Florida 27 Ohio 20 Georgia 15 Oklahoma 7 Hawaii 4 Oregon 7 Idaho 4 Pennsylvania 21 Illinois 21 Rhode Island 4 Indiana 11 South Carolina 8 Iowa 7 South Dakota 3 Kansas 6 Tennessee 11 Kentucky 8 Texas 34 Louisiana 9 Utah 5 Maine 4** Vermont 3 Maryland 10 Virginia 13 Massachusetts 12 Washington 11 Michigan 17 West Virginia 5 Minnesota 10 Wisconsin 10 Mississippi 6 Wyoming 3 Missouri 11 Total electors 538
Each elector casts one vote for President and one vote for Vice President. In order to be elected, a candidate must have a majority (at least 270) of the electoral votes cast for that office. Should no candidate for President win a majority of the electoral votes, the choice is referred to the House of Representatives. Should no candidate for Vice President possess a majority of the electoral votes, the choice is given to the Senate.
The Constitution allows each state legislature to designate a method of choosing electors. Forty-eight states and the District of Columbia have adopted a winner-take-all popular vote rule where voters choose between statewide slates of electors pledged to vote for a specific presidential and vice presidential candidate. The candidate that wins the most votes in the state wins the support of all of that state’s electors.
The two other states, Maine** and Nebraska**, use a tiered system where a single elector is chosen within each Congressional district and two electors are chosen by statewide popular vote. U.S. presidential elections are effectively an amalgamation of 51 separate and simultaneous elections (50 states plus the District of Columbia), rather than a single national election.
Candidates can fail to get the most votes in the nationwide popular vote in a presidential election and still win that election. This occurred in 1876, 1888 and 2000, the first time George W. Bush was elected. Critics argue the Electoral College is inherently undemocratic and gives certain swing states disproportionate clout in selecting the President and Vice President.
To illustrate the process, here is the map of the 2004 presidential election. The figures represent the number of representatives elected in each state.

Red: Republicans Blue: Democrats
Source: Wikipedia, the free encyclopedia.