The scenario is possible but not even a little bit likely. In the movie, with the electoral votes for the other 49 states (and D.C.) counted, neither candidate had a majority in the electoral college. The election came down to New Mexico's five electoral votes. But the election in New Mexico was a tie. In Texico, an error message had caused one vote to go uncounted, the vote of Earnest "Bud" Johnson. Bud's vote would determine the five electoral votes of New Mexico, and with it, the presidency. In the real world, if a state were tied after the initial count, there would be a recount, which would inevitably call dozens or hundreds of votes into question, which would then render the lone uncounted vote of the movie unimportant. A court or panel of judges acting as an election board would decide which votes would count. In some states (New Mexico and Florida among them), votes can still be counted after election day. If New Mexico were genuinely tied after all votes were counted, state law calls for the two tied candidates to settle the tie by a single hand of poker with no draws. If, after the electoral votes are cast, no candidate has a majority in the electoral college, the election would be decided by the newly-elected US House of Representatives, with each state's body of representatives casting a single vote. This bit concerning the House is covered in Amendment XII to the US Constitution, the scheduling of the decision being a matter of federal law (which, as it stands, places the formal processing of the electoral college results at a time after new term of office for the House begins).