Facebook The Vote

Iowa, New Hampshire, and South Carolina have marked the route to the White House for more than a generation. But in 2016, the path to the presidency will run through new territory -- your Facebook news feed. As the race begins in earnest, the world's largest social network is emerging as the single most important tool of the digital campaign, with contenders as different and disparate as Hillary Clinton, Ben Carson, and Sens Rand Paul (R-KY) and Bernie Sanders (I-VT), all investing in the platform already.

Thanks to powerful new features unveiled since the 2012 campaign, Facebook now offers a far more customized and sophisticated splicing of the American electorate. And, for the first time in presidential politics, it can serve up video to those thinly targeted sets of people. That unprecedented combination is inching campaigns closer to the Holy Grail of political advertising: the emotional impact of television delivered at an almost atomized, individual level. It makes the old talk of micro-targeting soccer moms and NASCAR dads sound quaint. "I can literally bring my voter file into Facebook and start to buy advertising off of that," says Zac Moffatt, who was Mitt Romney's digital director and whose firm now works for Rick Perry's campaign and Scott Walker's super PAC.