You really do have to hand it to Steve Schmidt et al on how they've managed to turn Obama's popularity into a liability. Just check out this bit of analysis from The Economist:
Mr Obama could certainly tone down the triumphalism: opting to make his acceptance speech not in the convention hall but in a 75,000-seater sports stadium seems like another mistake, akin to his hubristic rock-star’s tour of Europe.
I mean, it was one thing when Republicans managed to use John Kerry's war heroism against him. After all, Kerry left himself open to the attacks by basing too much of his campaign on his service record--especially when, among a good number of Vietnam Vets, he was a less than beloved figure because of his protests against the war. And if Kerry hadn't made that fateful decision to go windsurfing, I'm sure Karl Rove would have found some way to make his cycling or even his tossing a football on an airport tarmac into an issue against him.
But, in Obama's case, you'd think that his popularity--which is something extrinsic to the candidate--would be impossible to demonize. Sure, Hillary Clinton tried, with her digs at Obama for making nice speeches before big crowds, but those attacks ultimately fell short. It wasn't until the McCain campaign's celebrity ad--and the repeated meme in other McCain spots of Obama standing before adoring crowds chanting his name--that Obama's popularity came to be viewed as a sign of his own haughtiness.
So was it a mistake for Obama to go to Europe and move his convention speech to a football stadium? I doubt it. Honestly, if Republicans can manage to turn those things into strikes against him, I imagine they can take pretty much anything Obama does and use it to their advantage. I suppose that's fatalistic, but I think it's important for the Obama campaign to stick to its game plan and just accept that, whatever he does, the GOP is going to find some way to use it against him. At this point, that appears to be the GOP's greatest strength.