Though I've not crunched the numbers fully, something still kind of perplexes me about the state of the dem race at the moment. If Clinton is getting 20-25+ margins all across the south, and mopping up in the northeast corridor, and doing well in Appalachia outside of WV, and winning Illinois by a good margin... then how come the national polling is typically between 0-15 margins for Clinton? Given the state by state polling in these diverse states, one would expect Clinton to be pushing 20 nationally if not more unless Sanders was getting crazy high support in a few small pockets beyond just upper new england. Is everyone in Montana voting Sanders or something?
I think there is a reason to suspect that the national polls are relying on slightly looser likely voter screens than state polls, only because the state polls are probably able to use voter rolls and tighter screens while national polls have to be RDD.
