Re: Pennsylvania Vindication Edition
I think the simple answer is, Pennsylvania is the second oldest state. Old people surrounded by old people is almost certainly going to provide an echo-chamber effect. This reverberating "get off my lawn" echo, combined with the other demographic disadvantages of the region (from Obama's perspective) make it spectacularly difficult for Obama to win.
I would say that the ray of light is that this probably is not going to (necessarily) hold true in the general, as the "Clinton is mathematically dead in the water" notion hasn't penetrated very well into the mind(s?) of the general voting public, and she's still viewed as a safe and viable Democratic alternative to the old media/low-info Boomers and their elders. Once (if?) she's defeated in a visible and final way, a lack of seemingly strong and viable Democratic alternatives will probably push Clinton voters towards Obama.