When citizens head to the polls to cast their ballots, they're not actually voting for Barack Obama or Mitt Romney, but instead electing democratic or republican electors, who officially elect the next president.
With the exception of Maine and Nebraska, all states act on a winner take-all basis. That means whoever wins the most votes in that state gets all of the electoral votes. However, that doesn't mean electors have to vote with the state. Electors who vote against their party are called faithless voters, there have only been 9 of those in the past sixteen elections.
Critics of the electoral college say the process decreases voter turnout because of the risk of faithless electors. However, experts say the electoral college makes your vote count even more in a swing state like Ohio.
The number of electors for each state is based on the number of representatives they have in congress. A candidate needs 270 electoral cotes to win.
