The Electoral College

The Electoral College is how the President is elected.  The amount of members that each state has in the Electoral College depends on that state's total number of members in congress, both the House of Representatives and the Senate.  Therefore the states with the greater population receives more members in the Electoral College than the states with a lesser population.  This ensures that the more heavily populated receive more voting power however it also ensures that the underpopulated states also have a voting power.  If the presidential election were simply majority vote candidates would simply skip the states that have very little occupants compared to the larger states and jump right to one of the heavily populated states because they would win based on popular vote.  The Electoral College attempts to give every occupant of every state a reason to vote.
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This is the number of members each state has reserved for the Electoral College.  When voting for the President, people vote for a set of representatives that should, according to each specific party, vote for their desired candidate.  The views of these representatives is unknown, and is not necessary.  These representatives were voted for by the people of each state to vote for who the state believes should be the President.