Although he has been one of the Senate's strongest and most vocal advocates of the war in Iraq, leading recent debates against Democratic bills to set a timetable for withdrawal, McCain has also been one of the Bush adminstration's biggest Republican critics.
As far back as mid 2003, shortly after the invasion of Iraq, McCain was warning that the United States needed to send more troops to Iraq and more money to Iraq reconstruction efforts, or else face a deep and long-lasting insurgency that would threaten America's mission there.
Which, of course, is exactly what has happened. He was also a strident critic of former Defense Secretary Donald Rumsfeld, telling interviewers that he lacked confidence in Rumsfeld as far back as 2004 — meaty criticism for a top Republican on the Armed Services Committee.
"There's not enough (troops), and we are in a very serious situation, in my view, a race against time. We need to spend a whole lot more money to get the services back to the people. We need to get the electricity going, the fuel, the water. And unless we get that done and get it done pretty soon, we could face a very serious situation," McCain told NBC's Meet the Press on Aug. 24, 2003.
"Time is not on our side. People in 125-degree heat with no electricity and no fuel are going to become angry in a big hurry. The sophistication of the attacks on U.S. and allied troops have increased. And what we do in the next several months will determine whether we're in a very difficult situation or not, and there's still time, but we've got to act quickly."
Despite McCain's contrary position on how the Bush administration has fought the war, however, pollsters say the public never really picked up on the nuance: He has always been seen as a Bush loyalist on the war, which is increasingly unpopular. And that's problematic for his presidential campaign.
About the only praise McCain has given the Bush administration on the war followed Bush's decision to send 30,000 more troops to Iraq over the past summer. That may have contributed to the sense that McCain was one of the president's men, experts said.
"Six months ago, Republican voters felt that he was in lockstep with the president (on the war) and … he was just going off the edge for the cliff for the president," said Dick Bennett, president of the New Hampshire-based American Research Group.
This new ad, which is running in New Hampshire and on his Web site, coupled with the message McCain is taking to campaign stops, is designed to put new emphasis on McCain's differences with an unpopular president over an unpopular war. With it, McCain hopes to turn a neat political trick: Supporting the overall policy, while reminding people that he would have done it differently.
As for his claim that just "one man" opposed the strategy in Iraq, that's a bit of a stretch: Independent experts and many congressional Democrats have lavished criticism on the administration's strategy in Iraq.
But among his major Republican competitors for the presidential nomination, McCain is right. Former Massachusetts Gov. Mitt Romney has recently suggested that he, too, would take a different route in Iraq than the president, but McCain was clearly there first.