Garrick
Awesome, lid.
Tea Party may be to blame, but both parties have shifted, at least given the metrics we have so far
Depends on which time frame we're talking about here. Clinton's 3rd way Dems of the 90's were centrist, but the mainstream of the party is as far left as it was pre-Reagan.
The one thing I'll agree with is that the parties are more pure than they have been recent history. Very few liberal Republicans or conservative Democrats left.