Update October 24, 2012: We've created a new Electoral College Tie Finder that will let you play around with any combination of 11 battleground states. We're planning to add 2nd District in Maine and Nebraska (one electoral vote each) to this in the next couple days, as what limited polling there is shows both are pretty competitive.
Update September, 2012: The post below was originally written in advance of the 2008 election. We've updated the relevant dates for the 2012 election. Separately, a few people have asked which candidate would win the presidency should the vote go to the House. Based on a review of the current race ratings underlying our 2012 House Elections Map, Republicans would have control in 26 states, Democrats 11. The remaining 13 states are too close to tell. Note that this is based on 'safe' and 'likely' races being allocated to a party. If this were to play out, Romney would have the advantage in a tie scenario.
What are the most likely ties? For those curious about actual tie combinations for 2012, there are 32 of them if we assume 11 battleground states (FL, PA, OH, MI, NC, VA, WI, CO, NV, IA, NH). Some don't think MI and PA are true battlegrounds. We'll let the voters decide, but just for purposes of the example, if we remove those, we are left with 5 tie scenarios. Finally, if we give NC to Romney and WI to Obama, we're left with 7 states (FL, OH, VA, CO, NV, IA, NH) and a 247-206 Obama lead. If it plays out this way, there are two tie scenarios remaining. In the first, Romney wins all but VA and CO. In the second, he wins all but OH and NH. You can use the 'Road to 270' feature, which appears below the map on the home page, to see all tie scenarios associated with your own election forecast.
Another close election may be coming up in November. It is not difficult to create a realistic scenario where the electoral map on election night is 269-269. What then?
As our site URL says, it takes "270 to Win". If neither candidate gets a majority of the Electoral Votes, the election for President is decided in the House of Representatives, with each state delegation having one vote. Senators would elect the Vice-President.
It is important to note that an apparent tie on election night does not mean that there is actually a tie. The actual Electors meet on the first Monday after the second Wednesday in December (December 17, 2012) to cast their votes. Only about half the states have laws requiring their Electors to vote for the popular vote winner. It is possible that an Elector could cast his or her vote for another person. As long as that vote wasn’t for the other major candidate in the race, this wouldn’t be an issue --- neither candidate would have 270. However, imagine a scenario where a single Elector in a single state switched their vote to the other party --- the vote would be 270 -268. While very unlikely, it has happened before (most recently in 1968, although the election that year wasn’t close).If you thought the 2000 election was controversial, this outcome just might bring the Electoral College system to its knees.
More than likely, the election would remain undecided after the Electors voted.The new Congress meets in joint session on January 6, 2013 to count the electoral votes (this count happens whether the election is close or not). If neither candidate has reached 270 Electoral Votes, then the House and Senate take over and elect the President and Vice-President, respectively.
UPDATE 6/22: Based on some feedback, we may not have made this point clearly enough: It is the new Congress, that is inaugurated the first week of January, 2013, that will have the responsibility of breaking any ties.