I'm a conservative. I have voted for Newt Gingrich, Saxby Chambliss, Alan Keyes, Phil Gramm and Johnny Isakson in general elections and primaries. I'm supporting Fred Thompson's candidacy (if he runs).
I will vote for Giuliani against any Democrat in the field, and so will many other conservatives.
You might, but many will just stay home. Frankly, I haven't decided what I'd do in a Giuliani vs. RAT election, and I've never missed a vote in my life.