The election is still two years away, but at this rate, will there be any incumbent Democrats left in the U.S. Senate by 2012? Another high-profile Democrat has announced he will not seek re-election.

Sen. Jeff Bingaman (D-N.M.) joins Kent Conrad (D-N.D.), Jim Webb (D-Va.) and Joe Lieberman (I-Conn.) in announcing they will not face voters in 2012, which will be a tougher year for Democrats than 2010 ... and we know how well that went for the Dems.

Sen. Bingaman to retire - The Hill's Ballot Box