Like Barack Obama has said, someone who is attempting to be elected President of the U.S. ought to be able to do at least two things at once.

Neither Obama or McCain are on any of the committees or are in any position of responsibility to negotiate a bill acceptable to the majority of both houses of Congress. If there is a vote contemplated or scheduled that would interfere with their travel to Mississipi for the debate, then they should remain in Washington. But as of Thursday night, there were no Senate activities or meetings where they would be expected to be in attendance. Most of the negotiations are to be in the House, with the Senate awaiting discussions in joint committee.

There will ony be three debates--opportunities for voters to observe the candidates questioned by a professional journalist and to see how they present and defend their positions and plans. They could then immediately return to Washington. That's at least as important as hanging around the Senate cloakroom, or worse injecting themselves into negotiations where they are neither wanted or needed.