For example in 1976 a majority of the Republicans polled would have voted for Reagan for president. But if you asked Republicans to choose between Ford or Reagan in the primary, then Ford won.
I think Hillary will have a very hard time winning the Democratic nomination.
I think the moonbat core of the Democrat party wants to see her win the nomination, and so she will.
It will be difficult/impossible for her to win the general election -- unless there is a third-party spoiler in the race.
(Think John Anderson, think Ross Perot, think McCain's "hero" -- Bull Moose Teddy Roosevelt -- think John McCain!)