McCain -- the senior senator from Arizona and presumptive Republican presidential nominee -- has attended none of the six hearings on Afghanistan the Senate Armed Services Committee has held in the past two years, ABC said.

Obama, his Democratic rival and the junior senator from Illinois, sits on the Senate Foreign Services Committee. He was at one hearing on the subject in March 2007.

A McCain surrogate, Sen. Jim DeMint, R-S.C., said Obama should have scheduled hearings before the European Operations subcommittee, which he chairs.

"As the situation in Afghanistan grows more tense, it is time for us to hold a hearing on the mission there," DeMint said. "The success of Afghanistan is critical to the future of NATO and vital to our efforts to defeat al-Qaida and the Taliban."