In politics, the question is more important than the answer.
With that in mind, it's not surprising that Rudy did well. The last debate featured many questions about social issues. It was not surprising that Rudy did poorly. Tonight, their was one short segment on the Life issue. Conversely, there was a lot of time spent on terror.
If the most important question is: "Who can best keep us safe," Rudy wins. If the most important question is: "Who represents our conservative values," Rudy loses.
McCain and Romney went at it without mentioning names. But the Rudy vs. Paul back-and-forth was the most entertaining.