By Barbara Liston
ORLANDO (Reuters) - Republican presidential candidate Newt Gingrich called on a group of his supporters on Friday to correct mistakes or scrap altogether a newly released documentary portraying rival Mitt Romney as a corporate raider who cost thousands of Americans their jobs.
It was a dramatic turnaround for Gingrich, who has hammered front-runner Romney in recent days over his role in the 1980s and 1990s at Bain Capital LLC, which bought companies and overhauled them.
A fundraising group, or Super PAC, sponsored the documentary "King of Bain," clips of which are being aired in ads for Gingrich ahead of South Carolina's January 21 Republican primary election.
"I am calling on the Super PAC ... to either edit out every single mistake or pull the entire film," Gingrich said at a campaign stop in Orlando, backing off the video that had been central to his recent campaigning.
The Washington Post's fact-checking feature on Friday awarded "King of Bain" four "Pinocchios" - its worst rating - and called it a "highly misleading portrayal of Romney's years at Bain Capital."
The Post described the movie as "such an over the top assault on former Massachusetts Governor Mitt Romney that it is hard to know where to begin."
It uses footage of distraught middle-class Americans who blame Romney's deal-making for their woes and mixes images of closed businesses with clips of Romney that make him look vain, foolish or greedy.
Romney leads Gingrich in polls of voters in South Carolina. A victory in the state would make him three-for-three in the race to become the nominee to face Democratic President Barack Obama in the November election, after Romney won in Iowa and New Hampshire.
Gingrich finished fourth in both of the first two contests.
The fight between the two Republicans goes back to late December when attack ads run by Romney supporters knocked Gingrich off the top spot in opinion polls in Iowa.
"Somebody that is running for president ought to have the courage to stand up for the truth," Gingrich said.
Gingrich had defended the video earlier in the week, although he said he had no relationship with the Super PAC behind it or the film itself.
"If somebody who is very wealthy comes in, takes over your company, takes out all the cash and leaves behind the unemployment, I think that's not a model we want to advocate," he said on Fox News' "Fox and Friends."
Gingrich was in Florida to raise money and open a campaign office in central Florida, ahead of that state's January 31 primary. More than 200 supporters turned out to hear him speak.
(Editing by Patricia Zengerle and by Xavier Briand)