ABC News

Sen. John McCain this morning expressed deep concern over the tone of the campaign for the GOP presidential nomination on "This Week," admitting that it may actually be helping President Obama in his bid to be re-elected in the fall.

"I am concerned about that," said McCain, speaking from Afghanistan. "And I think there is reason to be concerned about it…I don't think I have seen one that was as personal and as characterized by so many attacks as these are."

McCain, R-Ariz., blamed the plethora of negative attack advertisements on super PACs which, following a ruling by the U. S. Supreme Court, can receive unlimited donations that can be used for attack advertisements.

McCain blamed the Court's "ignorance" for the new power super PACs now possess.

"I think it's a very tough campaign and I understand that, but the fact is that these debates and these kinds of negative campaigns have driven the disapproval ratings of all of the members up."

McCain is supporting his 2008 rival Mitt Romney in his bid for the White House and said he is confident that the former governor of Massachusetts "will succeed."