Will the 2016 Democratic Nominee be to the left or right of Obama?

[Psychic Octopus]

I'm genuinely curious. I think that a lot of displeased progressives may focus their attention on a "grassroots, insurgent-type" candidate again, as many obviously believe Obama has not governed with them. On the other hand, the Democratic establishment may force through a more electable candidate, with centrist credentials, as they will probably be fearful of not being to appeal to more conservative Democrats. With Obama not on the ticket, it seems fairly likely that black turnout is reduced, which will probably make North Carolina and Georgia more favorable to the GOP. And if the wrong candidate is nominated, several core votes (labor, latte, et cetera) may be turned off.

So, what do you (especially Dems) think the path forward is? A more moderate candidate, or a more liberal candidate?