I think it boils down to Clinton not being a good candidate - she's "the establishment", a woman, and has no charisma. You can't have all three and still win.

Obama had the "handicap" of being black and "a funny name" but has plenty charisma and was seen as an outsider. Trump has charisma (for some) and is an outsider. Clinton has no redeeming quality in the eye of the electorate, even many who voted for her did so to stop Trump, not because they believed in her.