Andrew Gelman has more election analysis showing that the popular perception of this election is just wrong. While the young were overwhelmingly voting Obama, the expected massive youth turnout appears not to have happened (it increased by only 1 point) and the biggest gain in new votes was among ethnic minorities which Obama carried to the tune of 96 % for African Americans.
Instead, the overall gain happened mostly as a result of a major shift in the political positions of the electorate. The entire United States electorate has basically shifted slightly left, meaning that the story of this election was actually that of an across-the-board rejection of the republican political agenda and the Bush era's culture wars. Clinton was right: it's the economy, stupid. That might actually mean that Obama's 50-state strategy and heal-the-divide rhetoric was playing into a shift that was already taking place, articulating and amplifying it. Synergy, baby.