By J. J.'s logic:
I haven't been following this too closely, but why would they Bradley Effect show up in certain states but not others? Especially when the states where it does show up in don't seem to have any sort of logical connection?
We don't know. That's just how magical and mysterious it is!
And what exactly is the definition for the Bradley Effect to occur? Obama underpolling by how much? Because otherwise there's no way to tell if it isn't just MoE noise, or even some other factor entirely.
J. J. basically defines the Bradley Effect as "A black candidate underpolling by any number."