And in the most likely scenario of "Known Statewide Democrat who hasn't lost his most recent Congressional run" vs. Lieberman vs. "Some underfunded Republican nobody has heard of"?
You don't think Rell will go for it in 2012?
If Lieberman switches to caucus with Republicans, Republicans will run a placeholder nobody - or endorse Lieberman. Even if Lieberman doesn't switch, CT Republicans are better off with Lieberman in office than a so-called "progressive" Democrat - so they still might run a placeholder nobody.
If Lieberman retires, Rell might run.