Let me see if I can explain this simply.
When Sen. McCain was doing his highly circumscribed senate investigation of lobbyist Jack Abramoff, Jack's then-firm, Greenberg Traurig, hired
sometimes McCain foreign policy advisor and most-times lobbyist Randy Scheunemann "for advice on handling the Senate investigation."
This was while Scheunemann was also lobbying for the government of Georgia.
McCain campaign spokesman Brian Rogers told the Times "he believed that Mr. Scheunemann was hired because he had worked in Congress for more than a decade and had experience with investigations, and not because of any ties he had to Mr. McCain."