Paul Waldman outlines what should be Obama's reply,
The argument would go something like this: "I said I would 'aggressively pursue an agreement to preserve a publicly financed election' with my Republican opponent. And I'm happy to have our two campaigns sit down and see if there is a way to make the debate between me and John McCain, within the publicly financed system. But as long as there are 'independent' Republican groups out there planning on spending hundreds of millions of dollars attacking me, it would be pretty foolish to lock myself into a spending limit that makes it impossible to respond. So I ask Senator McCain: Can you call off the right-wing hit squad? If you can do that, I'll be only too happy to say we should both accept public financing. But if you can't, I'm not going to sign away my ability to compete."