A Viable Third Party

[Shameless Lefty Hack]

I could envision a multi-party system something like the UK (well, England specifically) emerging in legislative districts in the US; districts that are currently one-party (urban and liberal suburban districts and Dems, rural and conservative suburban districts for the GOP) draw substantial challenges from an either more moderate or more radical party. So in my home CD, the CT 3rd, I could imagine you could field a challenger from a well organized social-democratic party to Rosa DeLauro. In the district to the west of that, I would imagine that you could have a more Liberal Democratic (the UK party, that is) candidate and a more traditionally left-liberal candidate. But that would take a lot of political developments that haven't happened here. 

The Presidency, short of an iron-bound regional party (à la Wallace or the Dixiecrats in '68 and '72, and 1948 respectively) is a victim of Duverger's law.