Candidates for the Republican party nomination in next year's US Presidential election have taken part in the final televised debate before the Iowa caucus early next month.
The largely rural midwestern state, which hosts the opening nominating event of the 2012 campaign, has become key to narrowing the field of party contestants.
Supporters of Republican front runners Newt Gingrich and Mitt Romney are hoping that a strong showing in Iowa will provide momentum ahead of the New Hampshire primary on 10 January.
Mr Gingrich came under sharp attack from his rivals during the debate where they pounced on his receiving up to $1.6 million in payments from troubled mortgage giant Freddie Mac as evidence that he has profited as a Washington insider from an enterprise that was at the heart of America's housing crisis.
Michele Bachmann said she was shocked that Mr Gingrich was being considered as a potential Republican presidential nominee after acting as a "lobbyist" for Freddie Mac.
Mr Gingrich insisted that he was not a lobbyist for Freddie Mac, and said: ''I think people have to watch my career and decide," ticking off a conservative record he said he built up as House speaker in the 1990s.
Mr Romney, who entered the debate having flung a series of charges at Mr Gingrich, let his rivals do the work for him during the early portion of the debate and insisted he has the ability to create jobs.
Former Pennsylvania Senator Rick Santorum noted that Mr Gingrich was not well liked as House speaker.
"The speaker had a conservative revolution against him when he was speaker of the House," said Mr Santorum.
He also subtly raised character issues about the thrice-married Gingrich, saying, "We need someone who is strong in the political and personal side."
Meanwhile, Mr Romney will get a major boost to his campaign when South Carolina’s Republican governor Nikki Haley endorses his 2012 candidacy.
Ms Haley, who was elected in 2010 with the strong backing of Tea Party champion Sarah Palin, is to endorse Mr Romney on the Fox News Channel programme "Fox and Friends," a Romney campaign official said.
Ms Haley had been courted by many of the major Republican candidates and her endorsement comes as Mr Romney plans to spend the next two days campaigning in South Carolina.
She could provide an important voice for Mr Romney in a state where Mr Gingrich holds a substantial lead in polls.
