You'd have to be kidding if you think he'd really switch. His blood is old line New England Republican Blue. To people like this, the Democrats are the party for the Irish and Jews and Communists.
Chaffee rated a 44 from the ACU for the past two years. That's about the same as Louisiana's John Breaux, who Freepers seem to be periodically hot and heavy for getting him to switch. If Breaux and Miller switched, everyone here would be calling the RINO's if the continued to vote as they do.
Chaffee, John Breaux, Zell Miller, Olympia Snowe, Arlen "Scottish Law" Specter, Ernest Hollings, Susan Collins, and Ben Nelson form the "mushy middle" of the Senate - ACU ratings between 35 and 65. The rest of the Republicans are more conservative. The rest of the Democrats and Benedict Jeffords are more Liberal. Even McCain hasn't made it down into the "Mushy Middle" yet, though he is trying.