One of the primary reasons that blogs emerged over the last seven years was as a reaction to, an attempt to battle against, exactly this narrative which the media propagated and Democratic institutions embraced -- that it is the duty of every Democrat to repudiate and attack their own base; that the truly pernicious elements are on the "Far Left", whose values must be rejected, while the Far Right is entitled to profound respect and accommodation; that "Strength" in National Security is determined by agreement with GOP policies, which is where "the Center" is found; that Seriousness is demonstrated by contempt for the liberal masses; that every Democrat must apologize for any statement over which Republicans feign offense.
Plenty of Beltway institutions already existed for the purpose of cheering on any and all Democrats no matter what they do. If that's all that blogs are supposed to do, then there is no need for them. From the beginning, blogs have been devoted to opposing Democratic complicity and capitulation -- to the lack of Democratic responsiveness to their supporters -- every bit as much as opposing GOP corruption and media malfeasance. That role is at least as important as the others.