A common dramatic technique in cinema and television...
...and American Politics!
But who cares about "angry liberals", really:
From where the DNC is standing, Obama doesn't have a credibility problem;
liberals have a credibility problem.
The sad thing about it, is that this pollster probably got it right, angry liberals are just experiencing stage 2 of the Kübler-Ross model, right now. Some have been trying bargaining (stage 3), to no avail (as an old proverb puts it, "the prettiest girl in the world can only give what she has," and the DNC already took that from her); others are already undergoing stage 4 (depression); soon stage 5 (acceptance) will follow.
Or as J.R. Ewing would put it:
Until then, liberals' place at the table will be little more than this:
Not that there is anything wrong with that. After all, rodeo clown is a respected occupation—better than being a liberal, actually, in many quarters, including the DNC, from what I understand.
Unless, of course, you are one of those who still happen to think that the Democratic party really has a socially liberal and progressive platform (in the tradition of Franklin D. Roosevelt's New Deal, John F. Kennedy's New Frontier, and Lyndon Johnson's Great Society) and president Obama truly is a social liberal (and not a neoliberal in the tradition of Ronald Reagan and Margaret Thatcher). It's OK, you are only experiencing stage one of the Kübler-Ross model. Nothing wrong with that. You are not alone. Many people do...at first.