What does size have to do with presidency?

Ann Althouse has a link to a very interesting chart comparing recent candidates.

The answer: we like them tall and not too thin. In all of the races where the shorter candidate won, he was stockier than the tall guy (think GWB and John Kerry).

So, what do we have here- Obama is tall, but very thin (at 6 foot 1 1/2 and 180 lbs), but McCain is very small, (5 foot 7, 165 lbs).

Is anyone else shocked that McCain is that short? My husband is 5'8", and I think of him as a pretty little guy (which I like, quite a lot). But I've always thought of McCain as pretty tall. He seems tall. And, maybe because he's skinny, and young, but I always thought Obama seemed somewhat short.

Does perceived size matter?