"If it isn't Obama I won't vote Democratic!"
This kind of threat that I have heard from some (small minority of) Obama supporters leaves me puzzled as to what they actually hope to accomplish by making that threat. Do they think they are going to make Obama look any better to people who are still undecided? To my mind the only think it does is make Obama supporters look petty and thereby cast a negative light on their guy.
If you make a personal decision not to vote for Clinton if Obama doesn't get the nomination then that is your choice. But it is not going to be a factor in how others will make their decision (and, if it is, it will be a decidedly negative factor).
Almost as bad are those who say I should vote for Obama because it means that their right-wing uncle will vote Democrat in the Fall. I'm sorry, but my personal choice will not be determined by the choices of others, ESPECIALLY the choices of right-wingers. I mean, is it really an endorsement of a "progressive" Democrat to say that they are more popular among people who are decidedly unprogressive? These kind of anecdotes just make me wonder how much of a Democrat Obama is.
I'm leaning Obama btw. I voted for him in the MoveOn primary. But this kind of crap doesn't make me feel good about it.