Rick Santorum was the longest of long shots when, five years after losing his bid for reelection to the Senate by 18 points, he spent much of 2011 campaigning for president in three early-primary states. But he campaigned longer and harder - albeit with less media attention, money, and staff - than any other Republican candidate. By the time Santorum barely won Iowa (as we belatedly learned), he had held nearly 400 town-hall meetings.
The rise of Santorum can be attributed to several key factors:
Media coverage: Santorum's universally unforeseen sweep of the contests in Minnesota, Missouri, and Colorado last week won him enormous attention on broadcast and cable news across the country.
A campaign that had struggled to raise $1 million over three months in 2011 raised more than $2 million in the 72 hours that followed that romp.
Electability: Santorum is the most electable conservative remaining in the race.
Despite Newt Gingrich's high name recognition and his history as a leader of the conservative movement, his baggage has proven insurmountable. Gingrich's only win, in South Carolina, came on the heels of two dynamic but unrepeatable debate performances, and he has been unable to unite social conservatives with fiscally conservative tea-party voters.
Santorum has solid, long-standing support among social conservatives, and recent polling shows he is winning more tea-party support. It helps that he opposed the federal bailouts that Gingrich and Mitt Romney supported.
Absence of gaffes: This campaign has seen several national front-runners: Donald Trump, Michele Bachmann, Rick Perry, Herman Cain, Newt Gingrich. But all of them were unable to sustain a burst of support in the harsh glare of national media scrutiny.
Santorum's campaign had been left for dead many times, but it conserved its resources, developed a unique strategy, and let its workhorse drive it while committing very few gaffes. When Santorum has been given an opportunity - as he was when Romney's campaign foolishly underestimated the potential impact of a Santorum sweep last week - he has seized it.
Solid debates: It's hard to overstate the importance of the televised debates in this campaign. While nearly every Republican candidate has had a bad debate or a cringe-inducing moment, Santorum's performances have been consistently solid, leaving audiences with the impression that he is intelligent, confident, and experienced. His tactic of lumping Romney and Gingrich together on such issues as bailouts and an individual health-insurance mandate has been particularly effective in setting him apart.
Timing: Santorum is the last of the anti-Romney candidates. And when you are the last to bat, you can be the last to score.
In 2008, John McCain benefitted from peaking at the right time, when he won New Hampshire and Florida, after faltering badly early in the campaign. Santorum never faltered; rather, for a long time, he never really got going. But he is benefiting now from peaking at the right time.
While the national media, pundits, and conservative leaders were flirting with the flavors of the month, Santorum was doing the grueling, unglamorous work of building an organization. That ultimately earned him wins in four of the nine states that have held contests.
Santorum has significant momentum. To maintain it, he will need to prevent Romney from winning both Arizona and Michigan on Feb. 28. He also has to prove that he can win a large, expensive state, and that he can take harder punches from Romney, which Gingrich was unable to do.
More important, he needs to raise $5 million to $10 million over the next two or three weeks to fund his efforts on Super Tuesday, March 6, and in large states later that month and in April.
What Santorum needs most, though, is for Gingrich to exit, which would allow him to consolidate the "anti-Romney" vote.
Not long ago, no one had high hopes for the Santorum campaign - except perhaps Santorum, his family, and his longtime consigliere, John Brabender. Now Mitt Romney's campaign is hoping to come up with an effective response. But how do you beat a candidate who held nearly 400 town-hall meetings and scarcely made a mistake?