Loeffler is the fifth person to quit a prominent position with McCain because of ties to foreign governments or other special interest groups, The Washington Post reported. Newsweek reported this weekend that his company, The Loeffler Group, had received $15 million for lobbying on behalf of Saudi Arabia and had worked for other foreign governments.
Last week, the campaign adopted a policy barring paid lobbyists or anyone affiliated with so-called 527 groups -- independent political entities -- from holding a position.
"Everyone is coming into compliance. To the extent that there are others that are dealing with this, then potentially there will be more activity on this," Brian Rogers, a McCain spokesman, said. "It really becomes a distraction from the issues we want to talk about in this campaign."
The number of lobbyists working with the campaign became an embarrassment when it was reported that two of them had worked on behalf of Myanmar's military government.