FORTUNE — Ken Mehlman isn’t a private equity investor, but he has been one of the industry’s most influential figures this year. As global head of public affairs for Kohlberg Kravis Roberts & Co. (KKR), Mehlman has spearheaded a campaign to defend his firm and its peers from attacks that have resulted from Mitt Romney’s presidential candidacy.
“Private equity is no longer private,” Mehlman quips in an interview.
Indeed, for the past year firms such as Bain Capital, which Romney co-founded, have been very much in the public eye, portrayed in ads and remarks by President Barack Obama’s campaign (and earlier, by Romney’s GOP rivals) as job-slashing, greed monsters.
As the former head of the Republican National Committee and a campaign manager for President George W. Bush, Mehlman is particularly qualified to help financiers shape their message in an election year. Mehlman’s main talking point? Private equity firms take the kind of bold financial risks that strengthen businesses in ways that benefit the American economy. “You can’t invest in large businesses around the world today unless you are willing to help provide a thorough understanding of who you really are, and engage around issues that affect things like the environment, workers, and local communities,” Mehlman explains.
It hasn’t been an easy sell. For starters, the men and women who run private equity firms are notoriously guarded; they don’t like talking to the media about anything, let alone about how their operations really work. Even Romney shied away from discussing specifics of Bain’s investments.
Mehlman’s strategy has been to work through the Private Equity Growth Capital Council, a trade group formed in 2006, to spread the word.
In its early years, PEGCC was considered so ineffective that some of its earliest member firms bailed (including Bain Capital), and its founding CEO was sacked in the summer of 2011. Since then, the group has sprinted to relevance — publishing data, putting out papers explaining private equity’s relationship with public pensions, and even producing a video series about private equity-backed companies.
And it’s Mehlman who is widely credited with the group’s new strategic direction, along with fellow PEGCC board member David Marchick (a former Clinton Administration official who now runs external relations for The Carlyle Group).
“Ken, and maybe to a bit of a lesser extent David, recognized early that we all had a lot at stake if Romney was the nominee,” explains a senior private equity executive. “They’ve really put in place something that we probably should have had long before this.”
Mehlman, of course, defers praise to others, including new PEGCC CEO Steve Judge and communications chief Ken Spain (a former National Republican Congressional Committee spokesman). But the initial vision mostly was Mehlman’s, with Judge and Spain deftly working out the details and translating it into action.
Private equity executives will long remember 2012 as the year in which they were reluctantly thrust into the public spotlight. And they will remember that Ken Mehlman helped keep the unwelcome glare from burning too badly.
A shorter version of this story appeared in the November 12, 2012 issue of Fortune.