By Steve Holland
SIOUX CITY, Iowa (Reuters) - Front-runner Newt Gingrich was braced for attacks from rival Republican presidential candidates at a debate on Thursday as they make their case one last time before Iowa launches the 2012 election season.
Gingrich, Ron Paul and Mitt Romney lead the field in Iowa less than three weeks before the state's Republicans decide on January 3 who they want as their presidential candidate. It is anybody's guess at this stage as to who will win.
Gingrich is trying to hang on to a slender lead in the polls and the 8 p.m. CDT (9 p.m. ET) debate in Sioux City may gave him a boost, since the former speaker of the U.S. House of Representatives has benefited from past debate performances.
But the fact that this is the last debate before the Iowa caucuses may increase pressure on Gingrich's rivals to press the attack against him and try to raise doubts about his conservative principles.
Gingrich, who has emerged from the pack as the key conservative alternative to the more moderate Romney, has vowed to remain positive despite being labeled "zany" by Romney and lambasted by Paul, a Texas congressman, as a serial hypocrite.
"I'm frankly taking the gamble that the American people actually care about solving our country's problems, not just beating each other up," Gingrich told reporters on Wednesday.
Already, Gingrich, a former speaker of the U.S. House, is showing some signs of fatigue among Republicans in this Midwestern state, an indication that they remain open to voting for someone else as a barrage of negative ads and verbal punches takes a toll on him.
A Public Policy Polling survey in Iowa this week said Gingrich's support had dropped several percentage points and was leading Paul narrowly by 22 percent to 21 percent, with 16 percent for Romney and Michele Bachmann at 11 percent.
"The Iowa caucuses are completely wide open, at an unprecedented level. The debates, combined with the lateness in visits and ad blitzes, have created a completely unpredictable scenario," said Tim Albrecht, spokesman for Republican Iowa Governor Terry Branstad.
Some Republicans here like what they are hearing from Gingrich.
"Newt Gingrich is smart enough, he's tough enough, he's experienced enough to take on the establishment in the Republican Party and win," said Kevin McLaughlin, the Republican Party chairman in Iowa's Polk County.
Paul, a libertarian House member from Texas who would love to upset the conventional wisdom by winning Iowa, has been particularly critical of Gingrich. He has denounced him as a serial hypocrite, a Washington insider who made up to $1.6 million from troubled mortgage giant Freddie Mac, some of it right before the housing market collapsed.
Romney, a former Massachusetts governor, wants to convince Republicans he carries the best hopes of defeating Democratic President Barack Obama in the election next November. Polls bear out that view.
Romney ran a new TV ad in Iowa playing up his fiscal responsibility: "We can't keep buying and spending and passing on debts to our kids. And I'll stop it."
Romney has never competed fully in Iowa but would like to slow down Gingrich in the state and give himself a better chance of victory on January 10 in New Hampshire, where his big lead has been slowly eroding.
In many ways, a Paul victory in Iowa over Gingrich would be viewed as a win for Romney, who has sought to lower his own expectations in the state after losing it dramatically in his 2008 presidential campaign despite a spirited effort.
Still Gingrich, with his plethora of ideas and willingness to challenge Republican orthodoxy, is tapping into conservative hearts in Iowa in a way that may push him over the finish line in first.
A victory here would give him a boost in New Hampshire, and provide important momentum looking ahead to South Carolina on January 21 and Florida on January 31. Gingrich leads in both of those Southern states.
"From the voters I talk to, it's clear that he's captured their imagination and he's the candidate they believe cannot just present the right message, which is critical, but also can win and govern effectively," said Will Rogers, who plans to volunteer for Gingrich after departing the campaign six months ago during a staff exodus.
(Editing by Bill Trott)