Senator Joe Lieberman ("Independent Democrat"-CT) has been vigorously shilling for Senator McCain - despite the fact that Lieberman caucuses with Democrats, and enjoys the Democratic majority's Chairmanship on the Homeland Security Senate Committee. I suppose that is part of a quid-pro-quo - given that Democrats have 50 Senators, and Lieberman helps them avoid a tied situation, with VP Cheney breaking the tie.
As part of the McCain-selling, Lieberman keeps attacking Senator Obama, to the extent that Obama apparently took Lieberman aside in the Senate recently to discuss Lieberman's reported weak denials of the false "Obama's a Muslim" rumors (Newsweek; via Blogrunner/Jake Tapper).
If true - that Lieberman offers the same weak denials of these false rumors as Senator Clinton - that further proves that Lieberman is just caucusing with the Democrats (a) to keep the Chairmanship privileges of the Homeland Security Committee; (b) because he has no sense of gratitude/shame (your pick). Per TPM, the Lieberman campaign back in 2006 "begged" Senator Obama to endorse Lieberman in the Democratic primary for the Connecticut Senate seat, after anti-war Ned Lamont entered the race. And anti-war Obama did - presumably because Lieberman was his "mentor" in the Senate. However, Lieberman lost the primary; per Kos and TPM, Obama didn't help Lamont much beyond an endorsement, a fund-raising e-mail sent out to a paltry 225-people in CT and $5000; and Lieberman went on to win the CT Senate seat.
Back in 2000, Lieberman - even while running as Gore/Lieberman for the White House - ran for the CT Senate seat. I thought this was a very bad idea - running for (Vice)-President is a full-time occupation as it is, without the added distraction of fighting for a Senate seat. Perhaps Lieberman wanted to make sure he had at least one elected position irrespective of the Presidential election - which does not inspire much confidence in his commitment to the Democratic Presidential ticket in 2000.
So... I would call Lieberman something very similar to Trader Joe, but surely one cannot call a US Senator that, can one?
And by the way - I am disappointed Obama didn't do more to help Lamont. Maybe that was Obama's way of repaying his mentor. At least, he didn't actively help Lieberman, unlike Mary Landrieu (D-LA).