They wouldn't beat Chaffee, because he's from a Rhode Island family dynasty. I was arguing that they would beat just about anybody else.
That said, you make a good point about Laffey winning in such a city, so perhaps he could win, (although I still find it unlikely, I think the only reason Chaffee won is his fathers name) and I was leaning toward dumping Chaffee anyway nomatter what. So I do believe that I would support his challenge.
I still think, however, that Chaffee will win the general as a R if he makes it through the primary, and that anybody else is a longshot at best, although you have convinced me Laffey's chances are a longshot, instead of just flat out impossible.
Lincoln Chafee won because of the family name in 2000 because no one knew anything else about him, since he had only been in the Senate for a few months, and before that had been the mayor of Warwick (which, BTW, gave Bush 32.35% in 2000 and 41.02% in 2004, so it's about as Democrat as Laffey's Cranston). In 2006, just about every Rhode Islander is aware of the fact that he's a complete idiot, and Republicans know that, unlike his father (who was liberal but at least was honest and honorable), he will backstab the GOP at every turn. I don't think that Chafee can go to the well one more time on his family name.
For more information on Chafee's flailing chances and Laffey's moderate credentials, see http://www.freerepublic.com/focus/f-news/1411655/posts