By Patricia Zengerle and Alina Selyukh
WASHINGTON (Reuters) - Republican Mitt Romney and his backers spent money more quickly in February than they took in, ending the month with less than half the cash they had at the end of the year and trailing far behind Democratic President Barack Obama's war chest.
Romney's campaign raised $11.5 million in February, according to financial disclosure forms filed on Tuesday, but spent $12.2 million.
Restore Our Future, the outside "Super PAC" supporting the former Massachusetts governor, took in $6.4 million but also spent $12.2 million, much of it on advertisements attacking his rivals in the race to become the Republican challenger to Obama in the November presidential election.
Despite spending at more than twice the rate of Rick Santorum, who emerged as his leading competitor in February, Romney has been unable to establish himself as a strong front-runner in the roller-coaster nomination race.
"Romney's been outspending Santorum anywhere from 5-to-1 to 20-to-1," said Norman Ornstein of the American Enterprise Institute, a conservative Washington think tank. "If he were with Bain Capital again and looking at the 'Super PAC Corp,' he'd probably dismantle it."
Together, Romney and the PAC were left with $17.8 million as of February 29, a sharp decline from the $24 million they had at the end of January and the $43.5 million war chest they had at the end of 2011.
Santorum raised $9 million in February and spent $7.9 million. His Red, White and Blue Fund Super PAC raised $2.9 million and spent $3.2 million. Together, they had $3 million in cash on hand. The Santorum campaign has debts of $922,488. It repaid the candidate for a $20,000 personal loan in February.
The frenetic spending, and lagging fundraising, in the drawn-out Republican nomination race does not bode well for the party's White House hopefuls.
Obama and his Democratic allies raised $45 million in February. His re-election campaign raised $13.9 million in February and spent $12.2 million, but had $84.7 million in cash on hand. But because he does not face competition within his party, Obama also has two joint funds with the Democratic National Committee.
Unlike campaigns, PACs have no limits on what they can raise or spend, so a few wealthy donors can dramatically affect a race. Republicans have proven far more successful at reeling in big donors during the nomination battle.
Priorities USA, a Super PAC supporting Obama, raised just $2 million in February, half of that from a single donor, comedian and talk show host Bill Maher.
THE CLOUT OF WEALTHY DONORS
Newt Gingrich's struggling campaign has been kept afloat largely because of billionaire Las Vegas casino magnate Sheldon Adelson. Adelson and his family have donated $16.5 million of the $18.9 million that Gingrich's Winning Our Future Super PAC has raised during his campaign.
In February, he and his family accounted for almost all of the PAC's $5.7 million haul.
Gingrich's campaign was in the red at the end of February, owing $1.6 million, while left with only $1.5 million in cash on hand.
Gingrich, a former speaker of the U.S. House of Representatives from Georgia, finished in fourth place on Tuesday in the Illinois primary, the latest in a series of poor performances at the polls. But he intends to continue his campaign to the Republican National Convention in August.
Ron Paul, a Texas congressman who trails well behind Romney and Santorum in most polls, raised nearly $3.3 million in February, and spent over $3.5 million.
Endorse Liberty, Paul's main Super PAC, had a terrible month, raising just under $282,500, a fraction of the $2.4 million it took in January. Peter Thiel, a co-founder of PayPal who had been the PAC's major donor, did not donate during the month.
Santorum's campaign also has a wealthy donor who largely kept it afloat before he won nominating contests in Colorado, Minnesota and Missouri in February to become Romney's main rival. Foster Friess, a wealthy Wyoming investor, has donated $1.6 million to the Red, White and Blue Fund, including $600,000 in February.
The former Pennsylvania senator also garnered the support of another big donor. Harold Simmons, a billionaire Dallas banker who has now invested in every major Republican Super PAC, donated $1 million to Santorum's PAC in February.
Romney has secured about half the 1,144 delegates he will need to become the Republican nominee.
In 2008, U.S. Senator John McCain clinched the Republican nomination on March 4 with victories in Ohio and Texas.
But this year's Republican battle, fueled by Super PAC money, is lasting longer, more like Obama's 2008 primary battle with then New York Senator Hillary Clinton for the Democratic nomination, which stretched into June.
"It's a hot contest and there are very entrenched feelings in the Republican Party as there were with the Democrats in 2008," said Jennifer Thompson, a political scientist at Virginia Commonwealth University.
(Additional reporting by Alexander Cohen, editing by Marilyn W. Thompson and Doina Chiacu)