If nothing else, this is a fun read.
Simply put: Montana is weird. An anti-Gay marriage Democrat against an anti-Paul Ryan Republican. And that goes for all of our elected officials. Our last Governor (a Democrat) had a Republican running mate. That same Governor, if I remember correctly, admitted to enjoying a beer or two, while driving, around his farm – yet still finally, in 2005, made drinking while driving illegal in Montana.
http://www.patheos.com/blogs/americanbuddhist/2012/11/montana-where-nate-silver-got-it-wrong-in-election-2012.html