The head of the Blue Dog Democrats in the House, Mike Ross, is that Democrats are facing "a terrifying reign of their own as liberal activists and unions keep hounding moderate members out of office." (emphasis added)
Well, let's get a few things straight. Most importantly, Blue Dog does not equal moderate. In Democratic circles we have three major types. Conservatives (Blue Dogs), liberals (Kennedy was a good example), and everyone else in between who could potentially be called "moderates.