Kerry does have more hair, mind you. Though it looks a lot like it might be a wig. I can imagine that speculation about that posibility could turn into quite a major issue in a Presidential election... Though I can't really think anyone would get a wig looking like that.

He'd look a whole lot better with a beard, the way Lincoln did. But I think they probably brought in some kind of unofficial addition to the US Constitution forbidding presidents from having beards.