While the networks focus on demographic explanations (white-black, man-woman), I think there is a case to made now that the regional draw of these two candidates is more deeply rooted in the recent political culture and history of each state. Obama's post-partisan, one America appeal resonates best in the states that have been dominated by Republicans and republican lite candidates (Iowa, SC, GA, AL, DE, CN). Obama is really cutting across the red states. On the other hand, Hillary is doing best among the blue states or trending blue states from the most recent elections (NH, NV, NY, NJ, MA). There are some slippery states for such a formula (TN, OK), but it might knock back the old political talk about identity politics and redirect the discourse to savvy political behavior and choices by the voters.

The post-partisan, bi-partisan argument favors the party out of power, so it is not really surprising that Obama resonates more with those states who see reconciliation as the path to local power. Clinton though seems more acceptable to partisans and state parties who control their local agendas.