I highly suggest a couple of approaches for his campaign:
First, the campaign needs to broaden the scope of their attacks on McCain-Palin, while not abandoning the "more of the same" theme.
To do so, the campaign must crystallize that the Republican "conservative" dogma and governing record has been destructive to the United States of America.
Their party has left us worse off than we were in 2000, both domestically and internationally. Most importantly, the Republican Party, supported by McCain-Palin, launched the most dangerous foreign policy blunder since Vietnam: the Iraq war. Make clear how the Republican Party has failed on economic policy, failed to respond to Katrina, and failed to utilize the goodwill after 9/11 for a better cause.
The campaign has made great strides to do so by pointing out that McCain is "more of the same" of Bush politics.
We must recognize that McCain really was a different type of Republican, and the best nominee that their party could have produced for this cycle. He was known for bucking his party on certain (but limited) issues. But, point out the strong rightward shift that he's taken, particularly by picking Palin, an inexperienced radical. The campaign's "Bush twin" message is good, but doesn't go far enough.
Secondly, the campaign needs to hammer them on judgment. Make clear that John McCain and Sarah Palin have specifically enabled the Bush administration in fumbling through years and failing on the policies mentioned. Both John McCain and Sara Palin voted for George W. Bush. They are responsible, therefore, for the results that their candidate produced. What kind of judgment is this? This isn't judgment that will make me feel safer as an American.
Thirdly, embarrass McCain and Palin for their positions on the issues and their records. McCain supports the Iraq war, which leads him to focus on "the surge." (More about that below.) He supports tax cuts at a time when the money is desperately needed for the war in Afghanistan and on domestic projects.
Sara Palin believes that God is mandating the Iraq war, that women must be banned from getting an abortion if they've been raped, even by a family member. She does not believe that we contribute to global warming. With regard to her record, she hasn't much of one. But, she supported spending $398 million dollars building a State bridge that literally lead to nowhere. All in all, she's not qualified to be President.
Finally, he must turn the Iraq debate around. Why in the world is McCain able to focus on his support of "the surge," which is merely a tactic of a wider strategic failure? Focus on his strategic decision to support the Iraq war. The media, including heavy hitters like Tom Brokaw, have adopted this surge thinking. Every question about Iraq focuses on the increase in troops. This is embarrassing. Instead, we should be trying to figure out how we got into Iraq in the first place, on a lie. There are no WMDs in Iraq.
I believe the Obama-Biden team will do what needs to be done, but time is running short. Let's get to work!