Key to the Obama campaign’s attacks on Bain Capital is the idea that the company was shirking its responsibilities to workers. We’re supposed to see Bain as a ruthless, profit-making enterprise with little concern for the lives of workers or the livelihood of a community. Implicit to the critique is that if Bain (and Mitt Romney) actually cared about creating jobs and improving the economy, it could have found ways to build wealth without closing factories and putting hundreds out of work.

This, however, is an odd conception of private equity. Bain’s job wasn’t to protect workers; it was to create the most wealth for shareholders under the least amount of risk. At times, this was terrible for workers, but it fundamentally wasn’t a concern. The Obama campaign’s exclusive focus on factory closings might play well in manufacturing states like Ohio, Michigan and Wisconsin, but it also opens Obama to the charge that he is waging an attack on “free enterprise.” It’s unfair, given the extent to which Obama has run a business-friendly administration (to the frustration of many progressives), but it has the potential for traction, since the Bain attack is centered on the destruction involved in the generation of wealth.

But there’s a way to account for this, and for that, we should look to Newt Gingrich’s campaign for the GOP presidential nomination. With the primaries over, Gingrich might insist that he failed with his attacks on Bain Capital, but that’s clearly not true; together with his debate performances, his attacks earned him a decisive victory in the South Carolina Republican primary.

Gingrich’s approach to Bain differed in the emphasis; rather than focus (exclusively) on the plight of workers, Gingrich challenged the idea that Romney was engaged in traditional, risk-taking capitalism. Instead, Gingrich argued in a news conference in January, Romney was a “vulture capitalist” who did more to extract wealth than create it:

“You have to ask the question, is capitalism really about the ability of a handful of rich people to manipulate the lives of thousands of people and then walk off with the money?” …

The former Speaker is making the case that, in contrast to good old fashioned businesses who make stuff, Romney and his ilk have instead gamed the system to create a soulless machine that profits from the misery of others.…

“I am totally for capitalism, I am for free markets,” Gingrich assured reporters on Monday. “Nobody objects to Bill Gates being extraordinarily rich, they provide a service.” What he instead is concerned about is when an investor receives “six-to-one returns, and the company goes bankrupt.”

The problem with Bain in the Gingrich narrative is that it made bad bets and escaped unscathed. With Ampad, for example, Bain amassed huge amounts of debt, paid $.002 for every dollar owed, and walked away with a $100 million return on its $5 million investment, even as it laid off hundreds of workers.

As Gingrich discovered, this resonates with voters, who don’t begrudge the wealthy but are angered that someone could take huge risks, fail and walk away with profit. Indeed, it’s the same disdain for golden parachutes that turned TARP into a political liability for President Obama, even if it was responsible for keeping the United States out of a second Great Depression.

There’s no reason for the Obama campaign to abandon its focus on workers, but it should also take a page from Gingrich and level its guns at Romney’s core argument that he is the embodiment of free enterprise. If it can portray Bain as something distinct from capitalism as popularly understood, the Obama campaign might find more traction with its attacks.