The biggest political party !

That would be the Utterly Disaffected, aka The Independents. Trending upwards in fact, while the Repubs and Demos fall steadily. The entire political class has to go. I can feel the wind behind the sails for our Balls Bluff Campaign already.

(thanks to Pew Research, via Talking Points Memo)

UPDATE: I just went back and reread Jack's last comment - I think we are both on to something if this chart is meaningful.