Exit poll data shows what a crushing victory this was for Romney. Among registered Republican voters, he got 48% of the vote, outpacing by over thirty points his nearest rival (Ron Paul at 15%). Romney's win did not come purely from a coalition of independents and moderate Republicans (though he did win registered independents as well, beating Paul 32-30). Self-described conservative and very conservative voters overwhelmingly preferred him to other candidates. Moreover, he won by eighteen points those New Hampshire voters who support the "Tea Party": Granite State "Tea Partiers" have claimed that Romney is their man. Ironically, Gingrich and Perry's hectoring attacks upon Romney's record in the private sector may help unify conservative support behind Romney.
Ron Paul's second-place finish was fueled by young people, new voters, and independents. Among registered Republicans, he didn't get above 15%, but independents and Democrats helped lift him to second place.
Jon Huntsman bet it all on New Hampshire and came in at around 17%---and could only get to 10% of registered Republican voters. Huntsman has said he's staying in, but he's hovering around 2% or 3% in South Carolina, Florida, and nationally. New Hampshire was the sort of territory most favorable to Huntsman, so those states will be a long march for him. We'll have to see over the next few days whether his numbers increase or not---if there's a bump, perhaps we could be seeing the beginning of Huntsmentum.
No doubt Team Santorum finds tonight's results a little unpleasant. But a near-tie with Gingrich for fourth place definitely keeps his campaign viable. Unlike either Gingrich or Perry, Santorum has performed very strongly in one of the first two key primary battles and respectably in the other. He goes into South Carolina with some vigor in his step. Unlike New Hampshire, South Carolina will be a key testing ground for his candidacy.