I think we'll see Perry stay strong in the last hour of the next debate. He did just fine until the last hour when he started crashing, his recent back surgery hasn't helped all that much.
It also would be quite tiring to anyone if all questions are designed for everyone on the stage to attack you. He had to spend most of his time on the defensive answering the same questions over and over.
I hope he learns how to turn all the attacks on him this week into an attack on Obama and not spend the entire time on defense.