It isn't going to happen. The country is far more interconnected than it was in the 19th century. The military is also far more federalized. The US military could crush the militias of any dozen states combined without working up a sweat so secession from a military point of view isn't really feasible the way that it was at the time of the Civil War.
The blue state / red state thing is also way overstated. It's not like 100% of the people in the red states are conservative and 100% of the people in the blue states are liberal. It's more like 60/40 in either direction and that's nowhere close to the kind of public support that would be necessary for secession.
Also, there aren't really any issues that separate one group of states from another. Issues like abortion and gay people getting married are issues everywhere - secession wouldn't change that.
And last, but not least, very large numbers of people just don't care that much about politics - they're too apathetic even to vote so you're certainly not going to talk them into supporting something that would involve giving up their currency and having to stop calling themselves Americans.