Cainmentum, baby!
I think Perry is stacking himself up for a Giuliani style loss. Yeah, the nat numbers still look good but he's lost Florida (and probably Iowa), he never had a shot in New Hampshire, and a late Cain/Newt dual resergence could spell trouble in South Carolina. First four primary losses could prove to be lethal.
I'll believe Perry's in trouble in Iowa when I see it. Forget the first 4, hard to see how losing South Carolina by itself wouldn't be fatal to a Perry campaign. If he won it though, losing Florida probably wouldn't be the knockout punch it was to Giuliani.