This could be a problem for Mitt Romney. An analysis of his political donors so far this cycle finds that 70% of them have already donated the maximum allowed by law.
The Center for Responsive Politics says Romney is having trouble finding small-dollar donors.
GOP presidential frontrunner Mitt Romney, actually, lagged far behind all other Republican candidates in terms of money from small-dollar donors.
While leading all GOP candidates is overall money raised, Romney's campaign collected just 6 percent of its second-quarter funds from donors who gave $200 or less -- $1.1 million out of $18.38 million.
Contrast that with President Obama's donors this election cycle. 47% of his total funds have come from donors who have given $200 or less, meaning those voters can give to the campaign again.