Watching McCain's speech, I find it striking how little emotion he's putting into it. Considering he just went from political oblivion to first-primary champion over the course of six months, you would think he would be a bit more triumphant.
It's probably because McCain is reading from notes. Mitt Romney, in contrast, pulled off a more emotional (for him) speech because he could pace around the podium flashing that Guy Smiley smile. He wasn't tethered to a podium, microphone, or legal pad.
It isn't like McCain didn't know he was favored to win. You would think he could have prepared a speech ahead of time. But then again, he is superstitious . Regardless, McCain has a national audience right now, and a national audience likes emotion. It likes public speaking. It likes people to look at the camera when they talk.