This

writer gives several reasons why Hillary Clinton should not pack it in.

She's tenacious, and I don't expect her to give up at all. She will stay in the race no matter how much Obama's campaign tries to get her out, no matter if the DNC chair puts pressure on her, no matter what the media says.

Clinton would also be much tougher for McCain to beat. The electoral math is against her, but she does have a lot of support among women, so the race will be far more competitive if she gets the nomination.

Sexism, though is still very much alive.