His state approval polls don't really seem to bad compared to the national ones. Could it be that he's doing so poorly in GOP strongholds that it's skewing the divide?
I have a feeling this election is going to be more like 2004. Obama isn't going to do great (40% or so) everywhere like he did in 2008. NC being the only competitive state in the South. CO and NM being the only states in the Plains/Rocky West being competitive.
Tom Jensen notes that Iowans have actually seen and heard the Republicans hopefuls, and that's the reason why Obama enjoys double digit leads against them.