Former Gov. Tim Pawlenty of Minnesota will report taking in less than $5 million, said a person close to his campaign, some of which may be earmarked for a future general election campaign and unavailable to Mr. Pawlenty in his battle with other Republican candidates. Even if it were all primary money, that would be far less than any of the first-tier Republican candidates raised during the early stages of the 2008 race, and underscored the difficulty Mr. Pawlenty faces in sustaining a strong challenge to Mr. Romney and the rest of the field.

Jon M. Huntsman Jr., the former American ambassador to China in the Obama administration, entered the race so recently that he is not required to report his second-quarter fund-raising until the fall, one of his campaign aides said. But the aide said Thursday that Mr. Huntsman had raised about $4.1 million for the quarter, though a substantial portion came from his own fortune.

Representative Ron Paul of Texas, in an e-mail solicitation to supporters on Thursday morning, said his campaign had raised about $4 million and hoped to raise more by the end of the day.