Mitt Romney faces another likely Southern setback _ this time in Louisiana.

Rival Rick Santorum is pushing for a strong showing in Saturday's primary, driven largely by the conservative religious voters who have propelled him to victory elsewhere.

"We think we're going to do well here. This state, I think of all the states in the Deep South, I think matches up with us well. It's a very conservative state," Santorum told The Associated Press as he campaigned here this week. "We're going to do better even than Mississippi and Alabama."

He needs the rebound and may just get it given that Romney is barely competing in the state.

Santorum was humbled in Illinois on Tuesday, where he lost to the former Massachusetts governor by a 12-point margin. Santorum was unable to broaden his appeal in that state much beyond voters who identified themselves as "very conservative," and most of his support came from Republicans in its southern, rural regions.

The former Pennsylvania senator also has been plagued by a series of problematic comments, starting in Puerto Rico where he spent days trying to explain his thoughts on whether English should be the island's official language. He then suggested he didn't care about the country's unemployment rate, a comment he later said he would have liked to rephrase.

And when he campaigned in Louisiana last weekend, the fiery Baptist preacher who introduced Santorum got the presidential candidate into some trouble when he said the U.S. is a Christian nation and suggested people who don't love America should "get out" of the country.

Still, that message didn't seem to hurt Santorum with the more than a thousand faithful who greeted him at Greenwell Springs Baptist Church, where nationally influential evangelical leader Tony Perkins regularly worships. Perkins invited dozens of pastors to meet with Santorum ahead of the service there, and urged them to tell their congregations to vote on Saturday.

"I like Rick Santorum because of his faith and conservative values," said Don Williams, the pastor at Hosanna First Assembly Church in Baton Rouge, an evangelical congregation. "Mitt Romney does not share my conservative values."

Those evangelical networks helped propel former Arkansas Gov. Mike Huckabee to a popular vote victory in the 2008 primary in Louisiana over Sen. John McCain.

Still, Santorum faces a potential challenge from former House Speaker Newt Gingrich, who has taken his flailing campaign _ and his pitch for low gas prices _ to oil-rich Louisiana. Gingrich placed second to Santorum in the recent primaries in Alabama and Mississippi.

Santorum strategist John Brabender on Tuesday urged Gingrich supporters to back the former Pennsylvania senator. "It's time for Gingrich supporters to get behind us if they truly want to have a conservative candidate," Brabender said.

Romney, by contrast, has struggled mightily with evangelical conservatives.

In Illinois, for example, Romney won 45 percent of "very conservative" voters who weren't evangelical, beating Santorum's 36 percent. But among very conservative evangelicals Romney lost badly, 56 percent for Santorum to 33 percent for Romney. Among "very conservative" voters who were not evangelical, the vote in Illinois was 45 percent Romney to 36 percent Santorum.

Romney is largely ignoring Louisiana as he looks instead to consolidate establishment support behind his candidacy and buttress the emerging consensus that he is the inevitable GOP nominee. He plans just one day of campaigning in Louisiana _ he has events Friday in Metairie and Shreveport _ and will spend Thursday courting members of Congress and other officials in Washington ahead of a Nashville, Tenn., fundraiser.

"We hope to do well wherever we are on the ballot, but we know we aren't going to win everywhere. We are hoping to pull as many delegates as we can out of Louisiana," said Romney spokeswoman Gail Gitcho.

But he's not spending money on TV ads to do it, the way he has in other states _ a sign of how little confidence his team has in victory here. That said, the pro-Romney group Restore Our Future is on the air on his behalf.

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."