Good grief. The more I read about this, the longer it sounds like it will take before we know who won. 
http://www.cnn.com/2012/11/06/politics/election-timing/index.html?hpt=hp_t1_1
If the margin separating Romney and Obama [in Ohio] is particularly thin, the election in that key battleground state could ride on absentee and provisional ballots. And that could keep the nation in suspense for a whopping 10 days.
http://www.cnn.com/2012/11/06/politics/election-timing/index.html?hpt=hp_t1_1