Newt Gingrich said today that the political establishment is fighting him because of fear over "the idea of a Gingrich presidency changing Washington."

"They are very frightened by the idea of a genuine outsider," Gingrich said on ABC's Good Morning America.

The winner of Saturday's primary in South Carolina also said he is "very comfortable" with the idea of releasing the contract he had with the Freddie Mac mortgage lender, but he did not make a firm commitment to do so.

Gingrich spoke as South Carolina runner-up Mitt Romney and aides sought to cast the former House speaker as a failed Washington insider whose beneficiaries included Freddie Mac.

The two rivals meet again in a debate tonight in Florida, which holds a primary Jan. 31.

In the meantime, Gingrich is trying to parlay his South Carolina victory into more campaign money needed to battle the well-funded Romney.

On his Twitter account, Gingrich announced that his initial "Knockout Punch Moneybomb" raised $1 million, and he asked backers to double that amount.

"We passed 1 million in less than 24 hours!" Gingrich wrote. "Let's go for 2 million. Donate today for the Knockout Punch in Florida."