I think the question is how does Mabin play. A disappointing opener, but he's got the talent to have a big bounce back and punish teams for picking on him. With Jewell the run defense should improve (in addition to added experience for our younger D-linemen).
I'm not a betting man, but it seems to me that Iowa rarely covers the spread. This series has been so wacky and unpredictable, I think I would take the points.