(CNN) - Sen. Joe Lieberman, the independent from Connecticut, is planning to announce Wednesday that he will not seek re-election, according to two knowledgeable Democratic sources.
The move by the former Democratic vice presidential candidate could add even more murkiness to the party's hopes of hanging on to its slim majority in the Senate in the 2012 election, especially coming on the heels of Sen. Kent Conrad's, D-North Dakota, that he will not seek re-election at the end of this term.
North Dakota's other Senate seat fell into Republican hands in the midterm election after Democratic Sen. Byron Dorgan announced his retirement. Rep. Earl Pomeroy, Democrat-North Dakota, meanwhile, lost the state's only at-large House seat in November, so Conrad's seat will be in major jeopardy.
While Lieberman is an independent he has aligned himself with the Democratic leadership for organizational purposes, helping to boost the Democratic majority on issues like health reform. But he has also frustrated party leaders on other big issues, leading one Democratic source to say privately that it's a "sigh of relief" for Democrats if Lieberman does step aside because the party would have a chance to elect someone who sides with them more often.
The race for his seat is wide open. Earlier on Tuesday former Connecticut secretary of state Susan Bysiewicz announced that she is planning to get into the 2012 Democratic primary for Lieberman's seat regardless of what the incumbent does. Reps. Chris Murphy and Joe Courtney are also considering Senate bids, while various Republicans are mulling their options.
A Lieberman aide stressed that the Senator made his own decision some time ago and it was not influenced by Bysiewicz's announcement Tuesday or any other maneuvering.
Lieberman, whose poll numbers have dipped mightily in Connecticut, is scheduled to officially announce his decision on Wednesday at 12:30 p.m. ET at the Marriott Hotel in Stamford, Conn.
"After many thoughtful conversations with family and friends over the last several months, Sen. Lieberman made a decision about his future over the holidays which he plans to announce on Wednesday," said Lieberman spokeswoman Erika Masonhall.
Lieberman won a fourth term in 2006 as an independent after losing the Democratic primary to Ned Lamont. After his re-election he still caucused with Democrats in the Senate, helping to boost their majority.
–CNN Senior Congressional Correspondent Dana Bash contributed to this report.
Joe's no dummy. He knows the gig is over. The Democrat Party he was once a part of does not exist anymore. He owes his current seat to all the Republicans that voted for him. Sorry Joe, you have no place left to run. Better to just retire than to pull an Arlen Specter and be humiliated.
You'd think he'd head to a proctologist after sitting on the fence and playing politics on so many issues.
It looks like the new guard is taking over for the fossil-guard. Joe's retirement won't be so bad on the old guy. We all get ready for the scrap heap sooner or later. Just one favor Joe ... take your old buddy John with you ... Please?
He was just an independent that caucused with the demcorats anyways. Independent in name only. He was the one that basically gave the demcorats their super majority.
Oh thanks to the Heavens!!!
Say it ain't so Joe.
I really like Joe didnt agree on everything but he truly wanted to work for the people. Unlike someone in the top spot now. He is a deceiver. Cons dont look like cons remember that.
Don't let the door hit ya where the good lord split ya!
Big deal. It's not like a republican has a chance to win his seat. It's a forgone conclusion that seat will remain democrat.
Yeah, Joe–you're a democrat. Claim to be an independent all you like, if you caucus with the dems, you're one of them.
I will miss you Joe, I really wish you would have gotten the Democratic Nomination in 2004.
Bon voyage old boy. Never trusted you anyhow.
Mr. Lieberman: You will be missed.. ... NOT..
I wonder how much he got paid not to run? This man only thinks about what's in it for him.
Lieberman's not yet run as a Tea Party Candidate...surely he's got one more face he could put on, ya think? Or has he completely squandered his credibility by party-hopping and then running as an Independant?
I hate to see Lieberman go. I liked him.
oh no - who will remind mcpampers what he is supposed to say?
Good Riddance! Good Riddance!! Good Riddance!!! Now he know he's got ZERO chance in the coming elections he decides he's not coming back...GOOD RIDDANCE!!!!
Excellent, getting rid of that DINO-hawk PITA is well and l-o-o-o-o-n-g overdue. Let's get a real Dem in there!
Thank god,ct does not want him.i voted against him in every election.what has done for ct.nothing.then threating assange and the times,it called violating our freedom of speech.
Kay Baily Hutchinson from Texas and now Lieberman.... is this possibly related to the shooting in AZ? The costs seem to be higher and higher; first, assassination of Character, and then, actual assassination. I hope this is not the reason.
That means: time to cash out. I can make uh I mean steal more lobbying.
He coulda been a contenda!
He was one of the few non-Republican senators who truly acted like a patriot time after time. I love his support of Israel, his strong stance against Islamic terrorism, and generally his display of old-fashioned common sense. I'll miss him.
Republicans should have no problem keeping Kay Bailey's seat and taking Conrad's. The Lieb's will be tougher but can be done. But we only need to take three. With a Republican vice president to break ties we'll have control of the Senate. Then we have to go about fixing the damage done since early 2009.
He wasn't going to get reelected anyway........