Republican presidential candidate Newt Gingrich is stepping up his defense of his lucrative consulting career, in part by arguing that he didn’t do very much to earn all that money.

In an interview late Thursday on Fox News, Gingrich said that he only worked about an hour a month giving advice to Freddie Mac, the quasi-public mortage company that paid him up to $1.8 million in fees.

Given previous reports on the size of the payments, that would suggest that Gingrich earned up to $30,000 an hour giving Freddie Mac strategic advice.

“I think less than maybe once a month, they would drop by,” Gingrich said. “We’d spend an hour. It would always start with me listening. I’d always say, ‘What are you trying to solve? What are your concerns? What are you trying to get done?’ And I’ve done this with many, many clients.”

Gingrich has been the subject of growing scrutiny in recent days over his myriad money-making ventures since leaving Congress, including lucrative consulting contracts like Freddie Mac and millions of dollars in membership dues from health-care corporations seeking access to the former House speaker.

His profitable role as an influence-broker poses a potential political problem for Gingrich, reminding voters that he is in fact a longtime Washington insider despite his outsider rhetoric. Gingrich also endorsed moderate policy positions during his time as a consultant on health care, climate change and other issues that may anger conservative activists.

Gingrich stressed on Fox that he has “never done lobbying of any kind,” but rather acted as a consultant and strategic adviser to many firms and groups.

He also said the Freddie Mac payments “were actually a relatively small percentage of the total income of Gingrich Group,” which was an umbrella corporation that handled much of his business. Gingrich promised to release more details about the Freddie Mac deal as early as Friday.

Following Bloomberg News reports on Freddie Mac, the Post reported Friday that health-care firms and industry groups paid Gingrich’s think-tank, the Center for Health Transformation, at least $37 million in dues since 2003 for “direct Newt interaction” and other access, according to the group’s member lists and dues schedule. The Wall Street Journal also reported Friday that the U.S. Chamber of Commerce paid Gingrich $120,000 a year for seven years to be an adviser.

In another report, the New York Times explored Gingrich’s financial ties to Gundersen Lutheran Health System of La Crosse, Wis., which favored Medicare reimbursements for doctors helping patients with end-of-life planning--an idea Gingrich later attacked as “euthanasia.” The New Republic had previously reported that Gingrich had close personal ties to Gundersen, which treated his father-in-law for lung cancer in 2006.

The think tank’s Web site listed Gundersen as a “charter member” in 2010, a ranking that generally carries a $200,000 membership fee, acccording to previous versions of Internet pages. The center stopped revealing its members sometime earlier this year.

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