The nation is rapidly polarizing. I honesty could see calls for secession/balkanization become relevant. Especially if trends continue and the EC goes blue, but Senate goes red and stays that way (more states are red than blue, republicans being more likely to ticket split is the only thing giving the dems a chance in the senate, and ticket splitting is declining). This results in a deadlocked nation where neither side can get anything done. Call me crazy, but that sounds like a recipe for trouble. Peaceful separation may be the best option. Neither side wants to be dominated by the other.
There's no radical difference between the Republicans and Democrats and their vision for the country's future.