In poll after poll, Rudy is the only one consistently beating all leading Dem candidates, until you tell them what Rudy stands for:
Kill Babies
Gay Marriage
Ban Firearms
Amnesty for Illegals
Big Government
Fascistism
I am sure you already know this, but here is the list of what Rudy stands for an accomplished (excellent summary with links, by areafiftyone):
http://www.freerepublic.com/focus/f-news/1790765/posts?page=56#56
Additional reading material:
Politics And Moralizing In Presidential Primaries
http://www.freerepublic.com/focus/news/1790774/posts
For Republican candidates, the toughest litmus tests are not about any actual policy alternatives, foreign or domestic, but about "social issues." What most social issues have in common is that they are none of the federal government's business, let alone the president's.
The federal government will never pass a law banning or permitting abortion, so a presidential candidate's opinion on that subject has no practical relevance.
The federal government will never pass a law banning or prohibiting states and religious organizations from defining marriage, and presidents cannot enact constitutional amendments, so gay marriage is not a federal issue, either.
Licensing of handguns is mainly a local issue, and no candidate is about to push for ending the federal ban on machine guns and assault rifles.
...polls show that a substantial majority of Republican voters approve of Giuliani's positions on all social issues, so the demand for ideological purity in these cases seems to require that candidates capitulate to a minority of the minority party. That does not sound like a recipe for success.
In the general election, however, the winner will emphasize concrete ideas about those issues a president can actually affect and be properly optimistic about the wondrous U.S. economy.