Another prediction: Neither Obama nor Romney will win a majority of the popular vote.
In the United States, the president is indirectly elected by the Electoral College made up of electors chosen by voters in the presidential election. In most U.S. states, each elector is committed to voting for a specified candidate determined by the popular vote in each state, so that the people, in voting for each elector, are in effect voting for the candidate. However for various reasons the numbers of electors in favour of each candidate are unlikely to be proportional to the popular vote. Thus in four close U.S. elections (1824, 1876, 1888, and 2000), the candidate with the most popular votes still lost the election.