I'm not voting for Hillary. Her tactics in the primary disgust me, I wasn't a fan of her back in the day, and her policies fail to move me any more or less than the other candidates. In addition, should she be elected, unless the Democrats manage to control both chambers by a veto-proof margin, I think Congress will be more gridlocked than a one-lane road to a Hannah Montana concert.
Having said all this, I don't blame her YET for staying in the race, though I'm scared of how far she'll go.
I don't think a long drawn out primary necessarily hurts the party having it. After all, Clinton had to come from behind in 1992's primary and still won, and Bush had to fight for a while to get it in 2000. It may not help, but it's not a sure-fire loss for the party, with one exception that I'll bring up later.
And, be fair - this is probably the only environment that Clinton realistically has a chance of winning the Presidency. She's not well liked, people have many and deep negative views of her, and in a 'normal' time she wouldn't have a chance. But given how suicidally stupid the Bushpublicans have been in trashing damn near everything, she does have a chance, now more than any. So why not stay and fight for as long as she can?
Now, the exception to my idea that hard fought primaries don't hurt the party is when the losing party decides to destroy the party to get selected. Will Clinton do this? I want to say no, but I have to admit I have some fear. I can see why she's staying in the race, and I hope that when she sees she will lose she won't decide to napalm the course as she leaves.