There could not be a north-south nor an east-west divide. The deep south would stick together and likely be their own country. I don't think the rest of the middle of the country would be able to get themselves together to form a single cohesive nation. I think they'd would break down to city-states with shifting alliances and internal wars against their own blue enclaves (and financial hubs). Plus, whatever alliance the formed, they'd still be landlocked and probably blockaded.