Warren won't run because she knows liberals don't vote for liberals. The establishment would never let a true liberal be the nominee.
Definitely. Which is why the last Democratic nominees were right-wing blue dogs John Kerry and Barack Obama.
Well to be fair, Kerry '04 wasn't Bush, and Obama was campaigning at Mr. Change. If Hillary gets the nomination in 2016 I can't think of any excuse for her supports who still claim to be liberals.
Because despite being a centrist, Hillary will advance liberalism more than electing a Republican would.
Ted Cruz is more liberal than Hilary
If you mean more Liberal in the TNF sense then yeah, but if you mean it in the real world sense, then no.