Lieberman going to bat for Coleman

In his latest break from the Democratic Party, Sen. Joe Lieberman (I-Conn.) is defending Republican Sen. Norm Coleman (Minn.) from Democratic attacks in one of the nation's closest Senate races.

Lieberman, the 2000 Democratic vice presidential nominee who caucuses with Democrats and gives them their two-seat Senate majority, disputes partisan attacks that Coleman conducted inadequate oversight of the Iraq war as the top Republican on the Permanent Subcommittee on Investigations (PSI).

"Any suggestion Sen. Coleman stymied Democrats' investigations into Iraq-related matters is unfair and unfounded," Lieberman wrote this weekend in an op-ed in the St. Paul Pioneer Press.

Since he lost the Democratic Senate primary in 2006, and later won a fourth term as an Independent, Lieberman has increasingly grown distant from his Democratic colleagues. As a foreign-policy hawk, he has repeatedly criticized the Democratic Party for trying to mandate a troop withdrawal from Iraq and for taking a "weak" stance on Iran. He has endorsed Republican presidential nominee John McCainJohn Sidney McCainCummings to lie in state at the Capitol Elizabeth Warren should concern Donald Trump 'bigly' Lawmakers toast Greta Van Susteren's new show MORE.

While Lieberman has donated money to the Democratic Senatorial Campaign Committee, he also has given cash to the reelection campaign of another endangered Republican, Sen. Susan CollinsSusan Margaret CollinsOvernight Energy: Perry to step down as Energy secretary | Future of big-game hunting council up in the air | Dems lose vote against EPA power plant rule Overnight Defense — Presented by Boeing — Pence says Turkey agrees to ceasefire | Senators vow to move forward with Turkey sanctions | Mulvaney walks back comments tying Ukraine aid to 2016 probe On The Money: Senate fails to override Trump veto over border emergency | Trump resort to host G-7 next year | Senators to push Turkey sanctions despite ceasefire | McConnell tees up funding votes MORE of Maine.

In his recent defense of Coleman, Lieberman cites his chairmanship by saying that he worked closely with the Republican and praising his work on the panel.

"To assert that Norm Coleman did anything less than a first-rate job on PSI demonstrates a fundamental misunderstanding of the subcommittee and ignores the substantial positive changes that his investigations have caused," Lieberman wrote in the opinion piece.