Small donors accounted for almost half of the money President Obama raised in 2011, according to a campaign research organization.

Obama received 48 percent of his total fundraising haul in 2011 from individual donors contributing an “aggregated … $200 or less,” totaling $56.7 million, The Campaign Finance Institute said in a news release. All of the small-donor donations of the Republican 2012 presidential candidates combined, former and current, come to $38.1 million.

“Because small donors can give again, and may be willing to serve as campaign volunteers, successful small donor fundraising can serve a political purpose that goes well beyond the reported dollars,” the institute said in its release.

Mitt Romney, long considered the front-runner for the GOP presidential nomination, has raised $56.3 million from all donors, CFI pointed out. Only 9 percent of his 2011 contributions came from small donors.

Other current Republican candidates for the 2012 nomination fared better. Newt Gingrich raised 49 percent from small donors, while Rick Santorum received only 32 percent from that community.

Buddy Roemer tops the list for the GOP nominees, with 100 percent of his donations coming from small contributors. Michele BachmannMichele Marie BachmannBachmann won't run for Franken's Senate seat because she did not hear a 'call from God' Billboard from ‘God’ tells Michele Bachmann not to run for Senate Pawlenty opts out of Senate run in Minnesota MORE came in second, with 60 percent of her contributions from small donors, and Herman Cain came in third at 52 percent.

Obama raised more than twice as much from small donors in 2011 as he did in 2007, when 22 percent of his $96.7 million came from small donors. The president also raised $33.4 million in 2011 “from donors who gave $1,000 or more” versus 2007’s $57.9 million from that same contributor category.

— This article has been corrected to reflect that 48 percent of Obama's 2011 fundraising haul came from small donors.