Regarding his lack of drawing power: Gifford Miller is a Whitle anglo Protestant who grew up wealthy and went to private boarding schools. I don't think most NY primary Dems feel that he really understands their problems. He simply doesn't have a built in demographic base at all, save for a few small pockets of old money in Manhattan. By contrast, Bloomberg is super rich, but he is Jewish and has a automatic base of people who will vote for him. Further, Bloomberg is able to build a coalition of white ethnics scared of Dinkins II and enough crossover "minorities" to win. That crossover of "minorities" all depends on who the candidate is- If Ferrer he gets more blacks and less latinos Weiner more crossover from both, Fields more latinos and less blacks etc etc.
Perhaps I am over stating the level of identity politics, but not by much.
Just one minor correction here: Gifford Miller is not a white Anglo-Saxon protestant, he's Jewish.