"John McCain does no favors for, nor gives no special treatment to, any lobbyist, even if they are a friend of his," Charles Black told CBS Face The Nation host Bob Schieffer.
Black said the reports would not affect the candidacy of McCain.
Also on the show was a discussion featuring two governors: Jennifer Granholm, D-Mich., and Janet Napolitano, D-Ariz., who talked about the latest campaign developments, including the announcement this morning that, much as he had in the last two presidential contests.
Napolitano said the Nader announcement was a "non-event," and said the increase in voters in primaries and caucuses demonstrated that the electorate is excited - and not pining for an alternative. "They're not looking for a third party candidate, like a rehash of Ralph Nader. They're invested in this race."
Granholm said she felt the issue of delegates from her state of Michigan and from Florida, which were not being counted owing to the earlier dates those states set for their primaries, would be resolved before the convention.
"I think there's a great desire to see Michigan and Florida [seated]. Nobody wants to alienate the voters of Michigan and Florida. It will be settled before then."
Read the full "Face the Nation" transcript here.