It's true, unless you think there is some type of female Bradley Effect at play.
91% of Republicans have a favorable view of Palin. In fact, Republicans were happier with their vice presidential candidate than with their presidential nominee.
http://www.rasmussenreports.com/publ..._helped_mccain
One reason is that somebody who is pro-choice will never win over a significant portion of evangelicals, who are the base of the GOP. I heard one evangelical put it this way: the economy changes, but values/principles of life do not. If you disagree on principles of life, there is little room for compromise