Hillary Clinton is not stupid. She knows at this point that we've gone too far down the path of this primary for both Obama and Clinton not to have their careers staked on November. If the Democrats lose in the fall, the losing candidate will be the most reviled figure in Democratic politics. But the second-place finisher in this rancorous primary will be a close second. It won't take long for finger-pointing to land on Clinton and/or Obama if the Democrats fail to take advantage of a clearly advantageous cycle. John Edwards or Bill Richardson could maybe come back in 2012 and run again. But Barack Obama? Hillary Clinton? This is it -- there won't be any coming back from a loss in November.
People who think that Hillary Clinton would want the Democrats to lose the White House in the Fall simply aren't thinking rationally and are allowing their (not entirely unfounded) dislike for her get in the way of an honest assessment of why she campaigning the way she is. Put simply, she just thinks she would be a better president and would have a better chance to win in the Fall. A lot of Democrats agree with her. I don't. You're free to disagree with her as well. But, please, leave the conspiracy theories to the nuts.