She stands a chance, for sure. Biden has proven to be too Trumpian for my tastes, name-calling, lying about obvious facts, and the whole subpoena thing. Bleh. But he's still the most likely.
The rest of the field that actually stands a chance:
Bloomberg is probably the worst choice of the five when it comes to winning the White House. He has a lot of negative things that could keep Democrats from voting for him. Notably wealth and "stop-and-frisk."
If Pete can somehow win Iowa or New Hampshire, or comes in second in both, he stands a chance. He needs a big win before SC, though, otherwise he's likely dead in the water. Still, a great showing from a young guy with limited experience.
Bernie/Warren could go either way, but they could also split the field enough to eventually let one of the others win. If one of them drops out early enough, the other will almost definitely get the nomination, but since they're both top tier candidates I don't see that happening.