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Republican presidential hopeful Mitt Romney greets supporters after addressing a primary night victory rally in Manchester, New Hampshire, January 10, 2012.
Republican presidential candidates trying to stop front-running Mitt Romney are raises tough questions about Romney's tenure as the head of the private investment firm Bain Capital.
Romney made a fortune running Bain. It specializes in buying distressed companies, making them profitable and then selling them. Newt Gingrich has been especially critical of Romney's role at Bain. A Super PAC that supports him is running ads critical of Bain, and they purchased a documentary that slams the firm for its practices.
For his part, Romney says he's proud of what he accomplished at Bain, and claims the investment firm created 100,000 jobs. It's difficult to unravel the details about Bain. As a private investment firm, it doesn't disclose a lot of information about its business. But we do know it's been very successful in making money.
Dan Primack, senior editor at Fortune Magazine and a specialist in private equity.