But the Texas congressman, who one PPP poll found within a lone percentage point of Gingrich among likely caucus-goers in Iowa, said his campaign was peaking at the right time.

"The momentum is building up," Paul said. "A lot of the candidates so far in this past year would come and go. You know, they'd shoot to the top and then drop back rather rapidly. Ours has never been that way. Ours has been very, very steady growth. And this last week or two there's a sudden extra growth."

Paul's campaign manager, Jesse Benton, said that Paul was benefiting from voters getting a chance to evaluate each of the presumptive frontrunners.

“As the campaign process plays itself out, and voters learn more about Newt Gingrich, the more people who are tired of the status quo in Washington are looking for someone with the consistency of record to tackle the tough issues,” said Benton in a statement. “Ron Paul has always fought for constitutional principles, limited government, and balanced budgets, he has the only plan that cuts $1 trillion dollars in spending year one and gets our country back on track. These are things that resonate with voters everywhere.”

Paul has been aggressively attacking Gingrich, airing ads in early primary states that question the former House Speaker's ties to troubled mortgage giant Freddie Mac and the healthcare industry.