The Center for Health Transformation, founded by Gingrich, provided the second contract a day after releasing a 2006 agreement for his services. The 1999 contract was renewed through 2002, and the 2006 contract was renewed for one year in 2007, said Susan Meyers, a spokeswoman for the center.
Also Tuesday, Gingrich said he did not want to continue debating his Republican presidential rivals if the audience isn't allowed to participate. His campaign said later that he would participate in forthcoming debates, regardless of the audience rules.
Gingrich, whose rise in the polls and come-from-behind victory in Saturday's South Carolina primary followed well-received debate performances, complained that people were admonished by NBC News moderator Brian Williams not to applaud during Monday night's debate in Tampa. The candidates will debate again Thursday in Jacksonville, Fla.
"That's wrong," the former House speaker told Fox News. "The media doesn't control free speech. People ought to be allowed to applaud if they want to. It was almost silly."
Disagreeing with his rival, Romney said that the rules for general-election debates were much stricter and that Gingrich had "better learn to debate in all settings."
Romney's advisers believe audience participation drove Gingrich's breakout moments in two South Carolina debates.
After the two candidates' night of mutual sniping in Tampa, each tried Tuesday to turn the arguments over their various business dealings to his own advantage. Romney's release of two years' worth of tax documents kept the focus on Romney's and Gingrich's money and how they earned it.
Romney's income put him in the top 0.006 percent of Americans, according to IRS data from 2009, the most recent year available. His net worth has been estimated as high as $250 million.
As the former Massachusetts governor relented to pressure and released more than 500 pages of tax documents, Gingrich kept up the heat, saying Romney was "outrageously dishonest" for accusing the former speaker of influence-peddling for government-backed Freddie Mac.
"I don't own any Fannie Mae and Freddie Mac stock. He does, so presumably he was getting richer," Gingrich told Fox News.
The specter of well-off Gingrich and wealthier Romney feuding over money matters pleased former Pennsylvania Sen. Rick Santorum, who lags in polls ahead of next Tuesday's Florida primary. He told MSNBC, "The other two candidates have some severe flaws."
Gingrich stood before thousands in a U.S. flag-draped airport hangar in Sarasota brimming with confidence about his chances of winning the GOP nomination. His campaign also said it had pulled in $2 million, mostly online, since winning Saturday's contest in South Carolina. Gingrich planned to pad his campaign account with a series of fund-raisers this week.
Records released by Romney's campaign show he closed a bank account in Switzerland in 2010, as he was entering the presidential race. He also kept money in the Cayman Islands, another spot popular with investors sheltering their income from U.S. taxes. But Benjamin Ginsberg, the campaign's legal counsel, said Romney "has paid 100 percent of what he owes."
Romney paid about $3 million on nearly $22 million in income in 2010 and indicated that his 2011 taxes would be about the same, $3.2 million on nearly $21 million in income.
In 2010, he donated a combined $3 million to the Mormon Church and other charitable causes. His effective tax rate was about 14 percent. For 2011, he'll pay an effective tax rate of about 15.4 percent, a level far lower than standard rates for high-income earners, reflecting the lower rate for long-term capital gains.
Gingrich's 2010 return, released last week, showed he earned more than $3.1 million and paid just under $1 million in federal tax, a rate of about 31 percent.