Though publishing it does feel a bit like piling on, this picture - an actual, real, Reuters photograph - does sort of sum-up the campaign. Your suggestions for a caption please!
UPDATE: Commenters point out that this was McCain pulling a deliberate "Doh!" type of face having initially tried to wander off the set in the wrong direction. So, unfortunate that the cameras caught him. And probably unfair for the whole world to blog it. Still, as I say, joke or not it does rather encapsulate the central campaign narrative: Obama cool, calm, collected; McCain crazy wee man.