Well yeah, because they know the GOP Base will not VOTE or support him. They know a McCain nomination would hand Hillary the Oval Office.
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Many warming unexpectedly to Clinton
CONCORD, N.H. - Don Schwartz, who describes himself as "a super-Deaniac progressive type," decided to back Hillary Clinton - whose centrist views, he concedes, do not necessarily match his own - for a simple reason. He wanted, finally, to be with a winner.