A race for the GOP presidential nomination that had seemed headed toward a quick conclusion just a week ago now seems more headed toward a protracted and expensive competition, thanks to Newt Gingrich's victory in Saturday's South Carolina primary.

Republicans in the Palmetto State dispatched the possibility of any tidy resolution to the primary campaign by handlng the former House speaker a 12-point victory over Mitt Romney, the former Massachusetts governor who had hoped to wrap up the nomination.

The candidates are now focused on Florida, which hosts a primary closed to Republican voters only on Jan. 31; the winner is awarded all of the Sunshine State’s delegates, but will also assume a degree of momentum from winning such a large contest in an important swing state.

"That’s the case you have to make in this contest – that you’re strong enough to compete in all of the states," said Kevin Madden, an adviser to the Romney campaign.

The contest in Florida is already shaping up to be an especially pointed one between Romney and Gingrich, the two of whom are already taking shots at each other at campaign events. They’ll confront each other directly at Monday evening’s NBC News/National Journal debate.

“What we know is that 75 percent of the party has consistently not wanted Mitt Romney,” said Rick Tyler, a former spokesman for Gingrich who now helps run a super PAC aiding the former speaker.  “Here in Florida, because Rick Santorum has essentially collapsed and Ron Paul is not competing, it's essentially a two-way contest. All I need to do is align Newt Gingrich with that 75 percent and Mitt Romney with Charlie Crist.”

The Romney campaign had treated Florida as a firewall even before losing the South Carolina primary. Almost 200,000 early and absentee ballots, which are expected to favor Romney, have been cast. And the state favors organization and money, the latter of which the Romney campaign has, as evidenced by a $2.3 million broadcast buy made this week.

The dynamics of the Florida campaign could allow Gingrich, though, to rally dissatisfied conservatives behind his candidacy and ride momentum from South Carolina – where his candidacy was resurrected for the second time this cycle – to compete and even win in Florida.

Tyler said that he expects Gingrich to win Florida, but asserted victory there wasn’t critical to the ex-speaker’s hopes of winning the nomination.

That’s because of the way this year’s primary calendar is set up.

Beyond Florida, the campaign also enters relatively dormant phase with several smaller caucuses and primaries through early March, mostly in states advantageous to Romney.

Nevada, a state where Romney has previously campaigned and which has a sizable Mormon population, hosts its caucus on Feb. 4, and Colorado and Minnesota host subsequent caucuses on Feb. 7.

Those are the only contests until the end of the month, when Arizona and Michigan host primaries on Feb. 28. Romney has an advantage in Michigan, where he was raised and where his father served as governor. Washington state also hosts a March 3 caucus.

Texas Rep. Ron Paul is also concentrating his efforts on winning some of these caucuses, where his enthusiastic supporters typically play an outsized role in similar contests.

That means Gingrich’s next big opportunity could come on March 6, this year’s “Super Tuesday,” when 10 states hold their contests – putting a number of delegates in play. It’s the results from those contests which could provide the best glimpse of how long the primary campaign will last, and whether Romney or Gingrich can finally score a decisive knockout blow.

“I think it's very important,” Tyler said of March 6. “But I think if Newt performs well in Florida, he'll do very well on Super Tuesday.”

The 10 contests on that day could favor Gingrich, since a number of them are in southern or more conservative states whose voters might be more inclined to support him. Gingrich won't be on the ballot in one of the states, Virginia, where he failed to qualify.

For its part, the Romney campaign has always stressed the primacy of winning delegates, and has prepared for the possibility of a drawn-out primary against a conservative challenger.

“The campaign was built for a very competitive primary contest,” Madden said. “I think we’re prepared to go all the way.”