Heh, now you've got me actually trying to pull off his voice, despite the fact I have little to no chance of doing so. And let me tell you: it really hurts.
Robert Loggia has a very gravelly voice, but he still manages to throw a lot of emotion in there. It'd be a hard thing for someone to get right.
Edit: You know, the more I try it, the more I think I'm at least able to get something barely recognizable as his mannerisms, if not his exact tone. It's not anything even remotely worth posting yet, but maybe if I keep fooling around with it, I'll be able to come up with something that doesn't utterly suck.