I will never vote for Ted Cruz/Mike Huckabee/Rick Santorum/Sarah Palin/Donald Trump in a general election, no matter how much you think I will, and I'd only do it in a primary to give a democrat I like an easy win (not ruling out Walker/Carson in every possible case, though it'd probably have to be them against a literal socialist, which HRC is thankfully not.). I've said I fear the far right more than the far left, and for good reason. The far-left would just spend us into horrible credit ratings in some bizarre attempt to make everyone equal. The far-right would do far worse, doing everything possible to lose jobs, then cutting as many entitlements as possible and throwing out the old, unlucky, and sick out onto the street to fight for food and health care.
As far as Hillary's primary opponents go, while I'd support Warren and Biden (in the primary, at least) if they were to run, I honestly don't think either of them will. So, that leaves:
An avowed socialist (Sanders)
A governor who I admittedly didn't have huge qualms with the policies of, but who can't get his chosen successor to hold the seat after him in an EXTREMELY blue state (O'Malley)
A one term Senator who nearly lost to a toxic opponent who made every possible gaffe in '06 (Webb)
A former governor who was unpopular but was at least able to convince voters to elect Raimondo, my endorsement for that race, to succeed him. (Chafee)
The first is just....ugh. It's perfectly clear the third would probably lose the general. So, that leaves the 2nd and the fourth. I feel roughly equally about them, and it's "cooler" to support Chafee right now, so my support (in the democratic primary) goes to him for now.
Not a single word of that explains or excuses this: