If you wanted to be a major-party presidential nominee three years ago, you would have been well-advised to pack a thick parka and extra-long underwear. In 2008, Democrats and Republicans in nearly three dozen states held a primary election or caucus in January or February. Those winter votes represented the culmination of a decades-long trend toward earlier presidential contests, a trend that Josh Putnam has chronicled in the blog Frontloading HQ. Next year, the trend will be reversed — at least to a point. It's possible that as few as four states — Iowa, New Hampshire, South Carolina and Nevada — will vote on both the Democratic and Republican side in January or February. The biggest reason for the shift is that Republican Party rules will punish states that hold a primary or caucus too early. Still, several states — Arizona, Florida, Georgia and Michigan — are threatening to vote in January or February, flouting those rules. For now, the calendar for 2012 remains in flux.