I've never trusted Zogby, and normally SUSA is gospel. When it comes to PA, Q'pac has at least as much experience and has been damn good in the past. (They nailed the Specter-Toomey primary, among other things.)
I'm saying that in this case, part of the crosstabs in this SUSA poll don't line up with reality.
Actually, the truth is that she needed to pull some of her eggs out of the Iowa basket and campaign harder in SC and for Super Tuesday. She went "all in" in Iowa, setting up high expectations, and leaving her unable to compete equally across the Super Tuesday states.
The staffer who argued in Spring 2007 for pulling out of Iowa altogether may have been right.