Washington (CNN) - Add Sen. Jeff Bingaman to the growing list of Democratic senators retiring after next year rather than run for re-election.
The four-term senator from New Mexico will announce later Friday that he will retire after his current term ends next year, a Democratic source confirms to CNN.
Bingaman joins Sen. Jim Webb of Virginia, Sen. Kent Conrad of North Dakota, and Sen. Joe Lieberman of Connecticut as members of the Democrat's 53 seat majority to announce they are not running for re-election. Lieberman, a former Democrat and current independent, is part of the majority coalition since he caucuses with the Democrats.
Two Republicans, Sen. Jon Kyl of Arizona and Sen. Kay Bailey Hutchison of Texas, are also not making bids for another term.
After learning of Bingamin's retirement, President Obama said in a statement “From his time in the Army, to his service as New Mexico’s Attorney General and Senior Senator, Jeff Bingaman has served this country and the people of New Mexico for more than three decades. He has been a tireless advocate for preserving America’s natural resources and promoting a clean energy future. Jeff has gained the respect of his colleagues on both sides of the aisle, in New Mexico and in Washington, and his voice on the floor of the Senate will be missed. Michelle and I offer Jeff our best wishes and deepest appreciation for his lifetime of service.”
Democratic sources tell CNN that the retirement announcements are part of a larger strategy by Sen. Patty Murray, chairwoman of the Democratic Senatorial Campaign Committee, to encourage her colleagues to decide swiftly on re-elections.
"The timing of these aren't incidental," a source tells CNN.
Democrats are trying to avoid what happened last cycle, when some senators announced well into the campaign season that they would not run for re-election. Sen. Evan Bayh of Indiana announced in February of last year that he would not make another bid, just four days before the filing deadline for candidates to enter the race. The early retirement notices could give the DSCC plenty of time to find strong replacement candidates for the retiring senators.
But Republicans say the retirements give the GOP a great opportunity to win back the Senate.
"It speaks volumes about the state of the two political parties that as strong Republican candidates step forward in key races, Senate Democrats in important battleground states are stepping aside. Like the earlier retirements in North Dakota and Virginia, Senator Bingaman's decision immediately presents another strong pickup opportunity for Senate Republicans," National Republican Senatorial Committee communications director Brian Walsh tells CNN.
Some Democratic strategists say that Rep. Martin Heinrich, who represents New Mexico's first congressional district, could be the strongest candidate.
Bingaman captured 71 percent of the vote in his 2006 re-election victory. Then Sen. Barack Obama won the state by 15 points in the 2008 presidential election. But the GOP won back the state's governor's office and a congressional seat in last November's midterm elections.
Twenty-three Democratic held seats and 10 Republican held seats are up for grabs in the next election cycle.
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