Like him or not, you at least know what you get with Chris Murphy. Lieberman cared about himself only, in the guise of bipartisanship. He lost his senate primary to Ned Lamont back in 2006 and democrats were ready to move on from him. Instead of bowing out, he ran as an independent/de-facto republican (since the GOP candidate was trash) that was able to take votes from every side and handicap Lamont.

If you are running on principals, he clearly didn't have any. You should run on what you believe in and that can be respected, but he just ran to win and not relinquish power.