Democrats expand primary map, spurred by social media

The shift reflects the new imperatives driving campaign strategy. With voters increasingly consuming news online, candidates are eager to go viral, which helps build their grass-roots and small-donor networks. This has made the feedback loop between the internet and television news the most powerful tidal force in politics, prompting campaigns to approach states as would-be soundstages for specific messages they are trying to deliver and constituencies they are hoping to reach.

One sign of a successful event, according to campaign aides working in this primary: Did cable news stations televise live from the venue?

“You don’t have to be in Des Moines or Manchester to have a viral moment and if that happens you’re in front of millions of people and can raise potentially millions of dollars,” said Tad Devine, a longtime Democratic strategist.