Yes way, he sure could do that.
Lieberman has always really disliked 0bozo, even before he became president. Remember when 0bozo got in Lieberman's face and tried to intimidate him in the US Senate back in 2008?
and I thought we didn't want RINOs.
Liebermen is no RINO. He is more of a DINO (Democrat In Name Only) on some issues. And he won't be becoming a Republican. He'll just vote with the Republicans for who becomes the majority party and on on some issues that's all.
So, you're just talking about his remaining an Indie and simply changing whom he caucuses with, not his party affiliation to GOP -- OK..got it. Plausible, but I still doubt he'd do it, because he's far left on everything but national security... but who knows? It'd be a "freebie," so to speak. Could you imagine (if McMahon wins) -- both CT senators with the GOP? Ah, sweet ironic justice.