Nate Cohn, New York Times: The Democratic midterm turnout problem is no secret. Young and nonwhite voters tend to stay home in off-year elections, leaving the electorate older, whiter and more Republican than in a presidential election. If there's any consolation for Democrats, it's that they will have an opportunity to do something about it. They'll spend millions to target Democratic-leaning voters over the next six months. And you would think that if anything could fix a turnout problem, it would be the vestiges of President Obama's vaunted ground operation. But not even the most sophisticated and well-funded turnout effort can fix this problem. Strong turnout operations can help Democrats at the margins. The Democratic turnout problem, however, is not marginal.