In any case, I don't think appointing a Republican would be a smart move for Rell and CT Republicans. Not only would it ensure a Dem pick-up of the CT governor seat at the first opportunity, it might also destroy Shays in 2008, and would have nasty conseqences for even the most popular of Vermont and RI governors: a realization, that a Rep governor means a Rep senator might make it impossible for anyone with (R) after his/her name to be elected to any governorship in New England. Even if she has a chance, I'd expect Rell to appoint a nominal independent. More likely, I'd expect her to simply sign whichever the Senatorial vacancy bill the legislature passes (whether it would require immediate election, or legislative confirmation or same party appointment, or whatever).
You've got to be kidding -- that's ridiculous. Connecticut isn't going to revolt over a moderate like Rob Simmons being made Senator. And they're not going to boot Chris Shays because someone appoints someone else to some other office. Whatever.
Rhode Island didn't revolt over Linc Chafee being appointed to the US Senate. And then Don Carcieri won election as Governor as an upset.
Despite what you think, New England doesn't instinctively hate Republicans unless they have a good reason to.