A trio of bipartisan lobbyists is opening up a new shop - and taking a gaggle of high-powered clients with them.

Chuck McMullen, Tharon Johnson and Blake Ashbee have left the law firm formerly known as McKenna Long & Aldridge to open Greenberg Traurig's lobbyist practice in Atlanta.

McMullen is a former top aide to Republican Rep. Tom Price. Ashbee is a former deputy to Gov. Nathan Deal who was appointed to lead the state's office of workforce development. And Johnson led Kasim Reed's successful bid for Atlanta mayor in 2009 and was President Barack Obama's 2012 southern regional director. He briefly flirted with a bid to lead the Democratic Party of Georgia this year before sticking with the lobbying gig.

"They already have a very experienced and robust national government affairs practice," said Johnson. "We’re just happy to add to what they're already doing."

They'll have their work cut out for them. Among the clients they said they are retaining are Microsoft Corp., which is always engaged in a tangle of messy regulatory issues; Spectra Energy, which is pushing a 157-mile pipeline through south Georgia; and MGM, which has proposed a $1 billion casino for downtown Atlanta.

The three are leaving another firm known for its bipartisan chops. McKenna Long, now known as Dentons, has a roster that includes former House Speaker Newt Gingrich, one-time U.S. Ambassador to Canada Gordon Giffin, Atlanta GOP rainmaker Eric Tannenblatt and ex-Vermont Gov. Howard Dean.

"This isn’t about them," said McMullen. "This is just a unique opportunity for us to build an Atlanta practice."