Essential reading from Sean Trende about the new demographic reality at the polls. Based on his back-of-the-envelope math, there are actually two reasons why there were more minority voters as a share of the electorate this time. One, the reason everyone knows: There were more minority voters, period. Two, the reason no one guessed: If current projections hold, there were many, many fewer white voters at the polls this year than in 2008. Had the same number of white voters cast ballots in 2012 as did in 2008, the 2012 electorate would have been about 74 percent white, 12 percent...