Newt Gingrich's top two fundraising advisers resigned on Tuesday, and officials said the Republican candidate's hobbling presidential campaign carried more than $1 million in debt.

The departures of fundraising director Jody Thomas and fundraising consultant Mary Heitman were the latest blow for the former House Speaker who watched 16 top advisers abandon his campaign en masse earlier this month, partly because of what people familiar with the campaign spending described as a dire financial situation.

These people, who spoke on the condition of anonymity because they were not authorized to discuss the campaign's inner workings, said the former Georgia lawmaker racked up massive travel bills but money had only trickled in since he got into the race earlier this spring.

These officials said that he is at least $1 million in debt. The current fundraising quarter ends June 30, and Gingrich will have to disclose his campaign finances by July 15.

He is personally wealthy and could fund his campaign out of his own pocket, at least in the short term, to keep his campaign afloat.

Gingrich refused to discuss the latest defections Tuesday night, dismissing them as "campaign gossip" that's being publicized to detract attention from his policy ideas.

"The whole point is nobody has a clue why they left," Gingrich told reporters after speaking to a tea party group in Savannah.

"Nobody has a clue whether they were failing to perform. Nobody knows anything except it's gossip."

He brushed off further questions about why the aides quit as well as about his campaign's debt load.

"I'm happy to talk to you about public policy," Gingrich said. "I'm not going to talk to you about campaign stuff."

Gingrich has insisted that he will not abandon his troubled bid and will continue fighting for the Republican nomination for president "no matter what it takes."