Romney is working to amass the 1,144 delegates it takes to earn the nomination at the Republican National Convention in August, and, right now, he's on pace to win the nomination sometime in June.
Louisiana's delegate rules say any candidate who doesn't get at least 25 percent of the vote is ineligible for any delegates. Anyone who wins at least that receives a portion of the state's 20 delegates — but no more. That could leave some delegates entirely uncommitted — and the top three competitors could come out with roughly equal delegate totals. In Mississippi and Alabama, for example, all three candidates took about a third of the vote.
In the days before Saturday's primary, Gingrich planned multiple campaign stops in Louisiana. Santorum campaigned there Wednesday.
A top issue in the oil-rich state is energy, and Santorum has tried to separate himself from his opponents on that subject.
"They know Romney has been bad on global warming, and Newt Gingrich has been bad on this issue," Santorum said during a campaign stop here.
After Louisiana, the race moves northward, leaving Santorum fewer opportunities to show strength against Romney. He's looking particularly to the April 3 contest in Wisconsin, a chance to show he can beat Romney in a non-Southern state.
But a win here, Santorum said, says "here's another state where we're probably going to be badly outspent and (Romney) can't win. He's not closing the deal."