He will continue several long-running fights in Washington, including higher taxes for PE firms from a potential change in the treatment of carried interest and increased registration and disclosure rules from the Dodd-Frank Act .

Mehlman was elected Thursday as the chairman of The Private Equity Growth Capital Council, the most prominent industry advocacy group for firms like TPG Capital, Silver Lake, Apollo Global Management, Carlyle Group and Blackstone Group.

Ken Mehlman, the public affairs chief at Kohlberg Kravis Roberts & Co. who was previously a leading Republican operative in Washington, is now the top lobbyist for the private equity industry.

Mehlman succeeds Mark Tresnowski, the top lawyer for Madison Dearborn Partners. PEGCC, launched in 2007, is also led day-to-day by president and chief executive officer Steve Judge.

Mehlman joined KKR in 2008 from Akin Gump Strauss Hauer & Feld, where he was a partner in the law firm's legislative and regulatory counseling practice. He is best known for his work on behalf of conservative politicians before: chairing the Republican National Committee and running George W. Bush's presidential reelection campaign in 2004.

Mehlman is also a prominent gay rights advocate and serves as a director of the American Foundation for Equal Rights.

Mehlman's primary responsibilities will be to "help expand the PEGCC's outreach efforts to educate and engage a broad set of stakeholders about the value of a vibrant and dynamic private equity industry," according to a statement from the association.

"I have enormous respect for the PEGCC's important work engaging with public policy makers to encourage more economic growth and retirement security for millions of Americans," Mehlman said. "I also share the PEGCC's goal of building a community of investors who seek superior returns while also emphasizing active, responsible governance, long term investment and measuring success in years not quarters."

Mehlman also credited Tresnowski for his work in helping block changes to carried interest taxes as yet and countering negative views of the private equity industry that emerged during former Bain Capital executive Mitt Romney's failed presidential bid.