To do so, he must avoid the talon wounds (self-inflicted and otherwise) that gashed Romney's latest run to make private equity palatable, if not indeed commendable, to the American electorate.
In a March 2012 Bloomberg Businessweek survey, 52 percent of respondents said they thought private equity practices were "mostly bad" for the economy, compared with only 27 percent who thought they were "mostly good." That said, polls also showed Americans largely agreeing that Romney's business experience would make him better in handling the economy.
A bartender at a fundraiser famously videotaped Romney telling donors that 47 percent of Americans are dependent on government, see themselves as victims and believe the government has a responsibility to care for them.
Still, there remains an open question in terms of how significant the "corporate vulture" attacks were in turning conceivably pro-Romney voters against him.
"I don't think that was the decisive factor in the presidential race," said Stuart Stevens, the former senior Romney campaign strategist. "I don't think this is why Romney lost the presidential race, and there is no data to indicate that is why he lost."
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Rauner spent 30 years with Chicago-based GTCR, retiring in late 2012 as the last of the firm's name partners. At the time, the firm's managing director Philip Canfield told Crain's Chicago Business that Rauner had become involved in so many civic and political causes, it was becoming a conflict-of-interest burden on the company.
Now, Rauner is hoping the firm won't be perceived the same way by Illinois voters.
"Bruce has said on the stump repeatedly that he knows that his private sector career will be an issue," said Rauner's spokesman Mike Schrimpf. "One of the things he is proudest of is that he and GTCR had been entrusted to invest the retirement fund for state workers and teachers and first responders, and they have produced tremendous returns for state workers and, as a result, have delivered value for taxpayers."
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Indeed, Rauner's investments have won plaudits from people on both sides of the aisle. But so too have they made him fodder for attack ads.
During the primary, Rauner's Republican opponents took aim at the $2.3 billion in payments GTCR shelled out to settle a series of wrongful death and neglect cases for a GTCR-backed nursing home company. Illinois state Sen. Kirk Dillard argued that Rauner was personally responsible for the deaths of nursing home patients because of staff and resource cuts that GTCR made.
Democratic Gov. Pat Quinn made clear that this line of attack would only continue in the general election. In remarks to the Chicago Sun-Times last week, Quinn zeroed in on Rauner having failed to disclose that a voting member of the state teachers pension board was being paid $25,000 a month in 2003 by GTCR as the board was considering a $50 million proposal from GTCR.
Quinn also took a broader shot at Rauner's wealth, comparing his one house to Rauner's "nine mansions." But Ben LaBolt, President Barack Obama's 2012 campaign press secretary, warns his fellow Democrat about misreading the playbook.
"Attacking a candidate's wealth or success is a mistake," said LaBolt. "Governor Romney presented his experience in private equity as his lead qualification to be president, and said that would be the same philosophy he would bring to governing. We made clear that being president is about more than the bottom line—it's making sure all Americans have a fair shot to succeed to work hard. Governor Quinn's message will be strongest if it sticks on that terrain."