I was just reading this article today. Remember in 2010 when Nancy Pelosi was seen as too liberal, and faced a Blue Dog leadership challenge? Shuler was basically a Republican who supported guns and opposed abortion and LGBT protections. Most who voted for him were conservative to some degree. Now, Pelosi's pretty much in the middle of the party, between centrist Dems and the party's emergent Left. Pretty interesting to see. America has changed and the Democratic Party has changed. And Trump/Q has replaced the Tea Party as the dominant radical force in the GOP, although there is probably some overlap.
http://www.cnn.com/2010/POLITICS/11/17/house.leadership/index.html