This "new" color association has always gotten my shorts in a bunch. I haven't found anything definitive...OTOH I haven't looked that hard.
I had read somewhere sometime back, the change was initiated by Tim Russert of NBC. Probably thought he was being cute behind that eternal possum-eatin'-poop grin of his.
I associate red now with those red-blooded Americans that love our country and are willing to sacrifice blood for it.
The depressing blue? Those liberals who suck off what red-America creates and the rights secured with its blood... and some confused people who bought their line of bull.
So I'm OK with it.