Party heresies

In A Liberal Long March? at Greater Democracy, Jock Gill calls for a sort of Gnostic Liberal movement to revitalize the left (although to my mind his emphasis on disintermediation seems to point more to the Protestant Reformation than to Gnosticism).
How ideologies grapple with heretical views may be instructive here, though it appears we’re at the beginning of an inquiry here and not near its conclusion.