In a race that has already seen dramatic twists and turns, former Pennsylvania Senator Rick Santorum – whose high-water mark was winning the Iowa caucuses in January – upturned the Republican leadership contest last night with his own display of election night drama.
By winning contests in Missouri, Minnesota and Colorado, Mr. Santorum punctured the inevitability that had come to surround (yet again) the candidacy of Mitt Romney. The idea that conservatives are coalescing around Mr. Romney, who may not be the perfect ideological conservative candidate but is arguably the most electable in a national contest against President Barack Obama, is once again in doubt.
Mr. Santorum's Tuesday night sweep only highlights the unease within the Republican base, which continues its search for a conservative alternative to Mr. Romney.
He has been trying for weeks to sow doubt in the minds of voters about the candidacies of former Massachusetts governor Romney and former congressman and speaker of the House of Representatives.
Mr. Santorum has argued that Mr. Romney's past policies on health-care reform and Wall Street bailouts make him indistinguishable from President Obama, while Mr. Gingrich, he argues, has a congressional track record that makes him unpredictable and a flawed presidential candidate.
If either becomes the Republican nominee, Mr. Santorum has said, President Obama will win a second term.
"I don't stand here to claim to be the conservative alternative to Mitt Romney. I stand here to be the conservative alternative to Barack Obama," he told cheering supporters at his victory speech in Missouri.
The Republican leadership contest is still shaping-up as a gruelling state-by-state contest for delegates. The Romney campaign was quick to point out that Tuesday night's contests did not actually award any delegates, a process that happens later.
But in a campaign where momentum can shape voter perception and win new donors, Mr. Santorum is riding high.
"Conservatism is alive and well in Missouri and Minnesota. We doubled him up here and in Minnesota!" he told supporters. At the time, the outcome of the Colorado caucuses was still in question.
The United States midwest has its strong Tea Party and evangelical Christian constituencies, which Mr. Santorum, himself the most socially conservative candidate remaining, would naturally appeal to. However, those same constituencies have not coalesced around Mr. Santorum in other states.
And even without the benefit of detailed voter surveys – no entrance or exit polling were done last night – Mr. Santorum dedicated his victories to the party grassroots.
"Tonight was a victory for the voices of our party, conservatives and Tea Party people, who are out there every single day in the vineyards building the conservative movement in this country," Mr. Santorum said in his victory speech.
Mr. Santorum, who is a devout Catholic and has championed the cause of the "working man," took a swipe during his victory speech at Mr. Romney over his comments last week that he was not concerned about the "very poor" because there was a safety net – food stamps, housing benefits and Medicaid – to help them.
Mr. Romney told the CNN interviewer at the time: "We have a safety net there. If it needs repair, I'll fix it... I'm concerned about the very heart of America, the 90-95 per cent of Americans who right now are struggling."
Last night, Mr. Santorum told the audience: "I care about the very rich and the very poor. I care about 100 per cent of America."
But Mr. Santorum cannot bask in his Midwest election glory for too long. The Romney machine that includes the candidate's official campaign, his surrogates, and the Super Pac Restore our Future is about to unleash a barrage of attack ads against Mr. Santorum in the run-up to key contests in Michigan and Arizona later this month.
Mr. Gingrich got a taste of the Romney machine twice. First in December, when it undercut Mr. Gingrich's surge ahead of the Iowa caucuses, and then again in late January when it upended his Florida campaign. Mr. Santorum has largely been spared.
To defend himself and sustain his campaign, Mr. Santorum will need a lot of money. In the all-important fundraising category, Mr. Santorum cannot compete with the war chest of Mr. Romney or even Mr. Gingrich's ability to pull in the $5-million campaign donations at a time.
But after his key wins Tuesday night, Mr. Santorum's fundraising will ramp-up and last night he did not have to look much further than over his right shoulder, where one of his biggest financiers, a beaming white-haired gentleman in the green tie stood.
Foster Freiss is a billionaire mutual fund manager and backer of social conservative causes and he has been a key donor to Mr. Santorum's Super Pac Red, White and Blue.
"We're heading to Michigan, we're really excited about that. We're also heading to Ohio. Super Tuesday is going to be a very, very big day for us. We've got organizations developing in every one of those states on Super Tuesday," Mr. Santorum told MSNBC this morning, referring to the nearly dozen contests that will take place on Tuesday March 6.