DES MOINES, Iowa -- Rick Santorum has gone from afterthought to X-factor in the Republican presidential field during the closing days before Tuesday's Iowa caucuses.
Through a combination of relentless campaigning, misfortune falling upon some of his rivals and a still-unsettled electorate, Santorum has risen from being a single-digit bottom-dweller to a third-place contender with aspirations of surprising front-runners Ron Paul and Mitt Romney on caucus night.
But is his surge too little too late? In this topsy-turvy campaign in which six candidates have taken turns at the top, nobody knows for sure. But the ex-senator from Pennsylvania is clearly enjoying the new attention after spending most of the year stumping through Iowa in near obscurity.
What a difference a bump in the polls makes. An NBC News/Marist College poll released Friday showed Santorum in third place at 15 percent among likely Republican caucus-goers, placing him behind Romney at 23 percent and Paul at 21 percent.
Fifteen percent might not seem like a big number, but it's a long way up from the 6 percent Santorum registered in a similar Marist survey in early December.
More importantly, Santorum has clawed his way past Newt Gingrich, whose numbers are fading under a barrage of negative attack ads, and Rick Perry, who is struggling to regain the confidence of caucus-goers after several poor debate performances.
"He's been slowly building a grassroots following," said Craig Robinson, editor of the Iowa Republican, a GOP newsletter, of Santorum. "He has the ability to challenge Ron Paul and Mitt Romney on caucus night. He's had quite a week. He's won the battle of the news cycle every night."
Robinson said Santorum's new status is a testament to his old-school campaign doggedness -- he has held over 350 town hall meetings and visited all of Iowa's 99 counties at least once -- and his appeal to Iowa's evangelical and Christian conservative Republicans, who have been shopping for a candidate to rally around.
"He getting that second wave, the splash created by the Gingrich collapse in the never-ending search by Republican conservatives for who's an acceptable conservative," said Lee Miringoff, director of the Marist College Institute for Public Opinion.
While Santorum's numbers here are looking up, his electoral future remains uncertain. Only 53 percent of likely Republican caucus-goers are strongly committed to a candidate, according to the NBC/Marist poll, and several Iowans who say they personally like Santorum and his message question whether he's a viable candidate in a general election.