Moreover, this business of "not knowing a person's positions" is, I think, a dodge. In fact, most of these pro-life people INDEED know Rudy's position and don't care if he can beat Hillary. And, we have poll after poll showing that some of these issues no longer have the clout they used to. We can deny it, but sometimes true is true. You say you trust the validity of polls, but then disregard the polls demonstrating that there is widespread lack of knowledge of Giuliani's positions. Every poll in which the question was asked has shown a large percentage of Republican voters either misidentify or do not know his positions on abortion, guns, and gays.
I'm not distrusting them at all: they say they support Rudy. What I question is the interpretation that they "don't know." Usually, what that means is, "I don't care, I'm supporting him anyway." But it's irrelevant if poll after poll (including poll after poll of Christians) has Rudy leading, and by significant margins.
The only way we'll know for sure is if a pollster ever asks a question like, "Even if Candidate X (or Rudy) is pro-choice, if the alternative is Hillary Clinton, would you vote for him?" Watch THOSE numbers!