| BILOXI, Mississippi
BILOXI, Mississippi Republicans Rick Santorum, Newt Gingrich and Mitt Romney battled on Monday for conservative support in Mississippi and Alabama ahead of presidential primaries that polls showed have turned into tense three-way ties.
The stakes are high for all of the contenders in Tuesday's Deep South contests, with Gingrich fighting to keep his struggling campaign alive and Santorum hoping for a knockout blow that would consolidate conservative opposition to front-runner Mitt Romney.
The southern primaries, originally seen as a fight between conservatives Romney and Santorum, gained a new edge with an unexpected strong showing by Romney in polls.
For Romney, a win in either state would be a landmark breakthrough that would signal his ability to capture conservative support in the party's Deep South strongholds and put him on a path to the nomination.
Public Policy Polling surveys showed a three-way jumble in each state. In Alabama, the three candidates were within 2 points of each other, inside the margin of error. In Mississippi, Gingrich led Romney by 33 percent to 31 percent, with Santorum at 27 percent.
"I do need your help," Romney told supporters who turned out in a rainstorm to hear him in Mobile, Alabama. "This could be an election that comes down to a very small margin."
Romney has opened a big lead over his rivals in collecting delegates to the nominating convention but has not been able to capture the hearts of conservatives who distrust his moderate stances as governor of liberal Massachusetts.
Even in Illinois, a Democratic-leaning state, Romney has more work to do. A Chicago Tribune/WGN-TV poll found him slightly ahead of Santorum, 35 percent to 31 percent.
His campaign argues that Romney's rivals cannot catch him in the chase for delegates, but Santorum raised the possibility that no one would manage to win the 1,144 delegates to clinch the Republican nomination before the party's convention in late August.
"If this race continues on its current pace, it's going to be very difficult for anyone to get to the number of delegates that is necessary to win the majority at the convention," Santorum told reporters after an energy forum in Biloxi, Mississippi.
He said a long, drawn-out primary campaign would allow the conservative alternative to Romney to rise.
"If we are successful here, it will have a very positive effect," Santorum said. "People in Mississippi and Alabama want a conservative for sure, they want a conservative nominee."
Gingrich has vowed to stay in the race all the way to the convention but he will face growing pressure to drop out if he cannot pull out a win in the Deep South primaries on Tuesday.
The Republican candidates are competing for their party's nomination to challenge Democratic President Barack Obama in a general election on November 6.
SPLITTING THE NON-ROMNEY VOTE
Alabama and Mississippi, which together have 90 delegates, have big blocs of conservative and evangelical voters who have moved toward Santorum in recent contests. The states award delegates proportionally.
Santorum beat Gingrich in Oklahoma and Tennessee last week, but Gingrich kept his campaign alive with a victory in his home state of Georgia, which he represented in Congress when he was speaker in the U.S. House of Representatives.
"Clearly the non-Romney vote is split between Gingrich and Santorum and clearly the vast majority of Gingrich backers have Santorum as their second choice," said Quin Hillyer, a senior fellow at the Center for Individual Freedom and a Mobile resident.
"If Gingrich were not in the race, Santorum would win Alabama by 15 points," he said.
The conservative pair appeared at an energy forum in Biloxi, where they criticized Obama for being unwilling to open more domestic areas and offshore sites for oil drilling.
"If we exist in a world where there is not peak oil, and we exist in a world where the United States can become the No. 1 producer in the world, then you have a total new array of possible policy strategies," Gingrich said.
He ignored his Republican rivals during his speech, but Santorum took shots at both Romney and Gingrich, saying they had fallen for liberal science on climate change.
Santorum criticized Gingrich for an advertisement he did with Democratic former House Speaker Nancy Pelosi where they sat on a couch together in front of the U.S. Capitol calling for action on climate change.
"We want to make sure we have a candidate going up against President Obama who can make the case about energy and our future, who can draw a sharp contrast about what's really at stake," Santorum said.
Santorum and Gingrich will both participate in a forum on Monday night in Birmingham, Alabama, but Romney is headed to Missouri for campaigning ahead of that state's caucuses on Saturday.
Romney's campaign and his allied Super PAC have been heavily outspending Santorum on the air in both states with negative attack ads, but Santorum said he was getting used to the barrage.
"We're used to being outgunned financially," he told reporters. "We're confident that we're going to do well here."
(Additional reporting by Steve Holland in Mobile and Susan Heavey in Washington; Editing by Alistair Bell)