Ramesh Ponnuru and Rich Lowry offer great advice in National Review:
Most important, McCain’s campaign needs a unifying theme. It so far has lacked one, which has made it seem carping and defensive, and has diminished McCain. Here again, he can emulate Hillary, offering a conservative version of her occasional theme of a “fighter for you.” In particular, he should be fighting for middle-class Americans against the lobbyists, institutions, and liberals who in various ways block their aspirations.
It is not enough, in other words, to offer wonky “reforms,” although that’s important. McCain has to tap into the anger and frustration of the American public. He has to complain that Washington is broken and argue that both parties have let voters down. He has done it before. In 2000, he was the feisty — even angry — crusader against Washington and the status quo. It wasn’t the ideal message for a Republican primary audience at that time, but now that voters desperately want such a candidate, McCain can’t quite find his old mojo.
The fighter theme would work on multiple levels. It would tap into the public mood of disenchantment with Washington and politics. It would suit McCain, who is at his best when expressing an outraged irascibility (getting angry is not something he usually has trouble doing) and whose sense of honor is genuinely offended by many Washington practices. It would communicate a certain vigor, perhaps mitigating concerns about his age. It would be in keeping with an aggressive anti-Obama campaign. It would excite conservatives because — much of the time — McCain would be fighting against a confirmed liberal with an adoring media, while the populism and the anti-Washington cast of the message would appeal to independents as well.
Americans are mad as Hell. Have at it, Mac!