WASHINGTON — A few hours before Rick Santorum captured two Southern states this week to rejuvenate his presidential campaign yet again, Mitt Romney said his rival's race had reached a "desperate end."
The question now, after victories Tuesday in the Alabama and Mississippi primaries, is whether Santorum will be able to parley those into a bounce big enough to propel him all the way to the Republican convention in August.
"If conservatives coalesce around Santorum, he now has that possibility," Republican strategist Kim Alfano said. "Romney cannot get it together. Why would he stop now? Romney's not going to wrap it up quickly."
The former Pennsylvania senator's path to the convention in Tampa, Fla., could lie in his candidacy sowing enough division within the GOP that it sparks a brokered convention, something that hasn't succeeded in American politics since 1932.
James McCann, a professor of political science at Purdue University, said such events harked back to the days of "smoke-filled backrooms" where political elites made party decisions.
A brokered convention can happen if no potential nominee gets enough support after repeated ballots by the delegates in the hall. That's when the political horse-trading begins. But McCann said the likelihood of something similar happening in this year's Republican presidential contest is slim.
"We've democratized the process so much, it's tough to imagine any sort of elite bargaining," McCann said. "I have to think the Republican leaders are saying, 'Let's not do that.' "
Still, if one thing can be gleaned from a campaign that gives new meaning to the legendary comedy bit "Who's on first?" it's this: While the Republican establishment — which is largely in Romney's corner — might be long past ready for this race to be over, the party's voters are not.
A new Pew Research Center poll this week found Romney with a 9-point lead over Santorum among voters who are registered Republican or who lean Republican. But neither candidate is doing well in matchups with President Barack Obama. Romney is down by 12 points and Santorum by 18, according to the survey.
To get to the convention with his campaign still intact, Santorum would have to continue to thwart Romney at every opportunity. His next chance will be Saturday at the Missouri caucuses, then next Tuesday in Illinois, possibly a pivotal contest.
Most observers think it's unlikely that he'll emerge at the end of the primary season in late June with the 1,144 delegates needed for the nomination. Romney already has nearly twice as many as Santorum, as well as much more money. He also is better organized.
But Santorum has passion on his side, a skill in articulating a message and an easy affinity with voters that so far has eluded Romney. And for someone who was little more than a political afterthought in the race not very many months ago, he has an unshakable conviction.
"All along he believed he had a chance if he hung in there long enough," said Terry Madonna, a Pennsylvania pollster and the director of the Center for Politics and Public Affairs at Franklin & Marshall College. "He would be the last conservative standing. I think he thinks he can win. I think he stays in until the last dog dies."
Crucial for Santorum is that Newt Gingrich gets out of the race so the primary becomes a game of one-on-one with Romney. But even after two losses in his Southern backyard, the former speaker of the House of Representatives has vowed to stay, a boon to Romney because Gingrich splits the conservative vote.
The contest is entering another potentially pivotal week.
The Republican Party holds caucuses Saturday in Missouri — a state where Santorum already won a beauty contest primary last month — and a telltale showdown looms Tuesday in Illinois.
"If you are a Rick Santorum, you have to win Missouri, because you have to have more wins to try to catch up," said James Harris, a Republican political consultant in Missouri. "Culturally, his message should resonate."
In Illinois, Santorum has to show he can negotiate the waters of a large, politically complex state.
Romney starts his campaign in the state with two big advantages: strong support from well-known local officials and Santorum's failure to field full delegate slates.
Romney also is expected to have a big edge in money and organization. Through the end of last month, he'd raised about $75 million, five times more than Santorum had. And Romney's public events tend to be smooth, delivering a crisp economic message and contrasts with Obama.
Santorum's appearances are hodgepodges. In Michigan last month, he promised to unveil a 10-point economic program — late on a Friday night — but stopped after No. 4 and talked for an hour. The next day in suburban Troy, Mich., he railed against Obama, calling the president a snob.
In Illinois, Republicans will choose delegates throughout the state, and Romney is banking on the names being familiar to voters. Even if people are reluctant to endorse him, they could be inclined to vote for delegates with familiar names.
State Treasurer Dan Rutherford and former U.S. House Speaker Dennis Hastert are among them. Romney's backers are pushing his business experience and ability to work with others, a clear bid to win moderates.
Whether this works is another question.
Santorum and Gingrich could harness the anger a lot of voters feel after four years of economic frustration. Gingrich has an ambitious schedule in the coming days of campaigning in the Chicago suburbs.
Santorum is expected to concentrate downstate in rural areas and small towns
"It looks like social conservatives are keen to stick with Santorum for the present," said Brian Gaines, a political analyst at the University of Illinois. "He's telling anyone who will listen that the race isn't over and that Romney can't win enough delegates to wrap up the nomination ahead of the convention."
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