John McCain is simply playing politics.
He wants to become president, and to do so, he needs to win the primary nomination. If you notice, ever since he's been speculated to run, his policies have begun to shift towards the right. Duh, you can't win a Republican primary if your not very Republican.
5-10 years ago John McCain was a rebel. It would seem that he would cross party lines over and over on certain issues. You really couldn't predict how he would feel about things. On one hand, he takes a strong pro-life stand, a spitting image of a right winger. However, he has been known to eliminate pork from bills going through the house. Here's a good article if you don't know what I'm talking about.
McCain Calls to Reform Pork Barrel Politics - washingtonpost.com
He's trying to convince the Republicans that he's not going to abandon the party platform, or isolate the Republicans... especially with the new liberal swing in congress.
To do this, He's done several uncharacteristically John McCain moves. First off, he's taken a strong opposition to gay marriage (his biggest flaw IMO). Secondly, He's supporting a surge in troops adamantly, even going as far as saying that the new plan is working ( and some initial signs suggest that he may be right). He's trying to get into the public eye and win the approval of the Republicans (and not necessarily the American people... yet).
Right now it's waayyy to early to count McCain out, but his lack of fund-raising isn't promising.