The Anger Market is only so big.

Dick Morris's analysis of the trouble that Kerry is in seems pretty convincing: New York Post Online Edition: postopinion

The polls already have shown how Kerry's own voters break almost evenly on the issues, with half supporting the war in Iraq and half opposing it, and almost equal numbers saying we must stay the course as say we should bring the troops home.

So Kerry can't use issues to hold his own in the debates: Whatever he says will antagonize some of his base. And now it's plain that he can't rely on personal popularity to hold them, since most are just voting against Bush.