Out of over 17,000 electors fewer than twenty have ever strayed from the popular vote and none of these voters have ever decisively determined a close election.
Another element of the Electoral College is the use of a "winner takes all" concept in all but two states (Nebraska and Maine). Under this "winner takes all" concept, the candidate with the majority of the popular vote for a particular state takes all of that states electoral votes, if there are only two candidates running. Under the scenario that there were three candidates running for the office of President, the individual with a plurality of the popular votes would win all of the electoral votes of that state. Therefore, even if a candidate won less than fifty percent (50%) of a states popular votes (with three candidates running), that candidate could still receive all of that states electoral votes. The other states mentioned who do not use the "winner takes all" concept, use a proportional allocation of the number of popular votes cast for each candidate, and distribute the electoral votes accordingly. .
Should two candidates tie with the same number of popular votes in a specific state, the first step would be to recount the states votes to make sure the results were accurate and that there was actually a tie. In the rare instance there was still a tie, after the Secretary of State had certified the results, Federal law would allow the state to hold a run off election to determine the winner, and ultimately cast the electoral votes.
Under the scenario that there is a tie in the number of electoral votes received by two candidates, the selection of the President would be handed over to the House of Representatives. The twelfth amendment lays down the process by which this is to take place. The house would select the President by majority vote, choosing from the three candidates who received the greatest number of electoral votes.