For two of the GOP front-runners, their supportive super PACs raised more money and have more cash left in the bank than the candidates' own campaigns. Helping their efforts are major financial gifts from wealthy business executives, whose contributions can be essential to the groups' continued operations.

Mitt Romney-leaning Restore Our Future and Newt Gingrich-supportive Winning Our Future raised a combined $17 million last month and spent nearly $24 million during that same period. That financial strength allowed the groups to splash the airwaves in key primary states with millions of dollars in TV ads.

The proliferation of new super PACs continues to underscore how the groups, which can raise and spend unlimited sums, are influencing the race. The groups' fundraising last month offers a periodic behind-the-scenes glimpse into the identities of the rich supporters who will help elect the next president, along with details on how the millions of dollars they donated have been spent.