"Basically, do I want out or do I want to stay? I want to make a difference," Manchin said on CNN's "State of the Union." ''The Senate gives me a great vehicle to make a difference in the world, and in my country and in my state. With that being said, if I don't see changes being made, if I don't think that I'm being productive and contributing to something in a positive manner, I've got to evaluate where I'm at and where I might be most effective."
Manchin is considered the most conservative Democrat in the Senate and has sought to work with Republicans, most notably on unsuccessful legislation last year to expand background checks on firearm purchases as a way of curbing gun violence. He has co-chaired a group called No Labels, which promotes bipartisanship and problem-solving.
If Manchin decides to depart the Senate before his term ends, it could present an opportunity for Republicans in West Virginia, which has taken a conservative turn in recent elections.
Heading into the 2014 Senate election, President Barack Obama remains unpopular in the state and polls have shown Republican Rep. Shelley Moore Capito leading Democratic Secretary of State Natalie Tennant for the seat of retiring Democratic Sen. Jay Rockefeller.
West Virginia's constitution prevents a governor from serving more than two consecutive terms, meaning Manchin could attempt to succeed Democratic Gov. Earl Ray Tomblin when his second term ends in January 2017.
Manchin, who was elected governor in 2004 and won a second term four years later, said it was "one of the most productive periods of my life. I felt more productive as governor than any time in my life in anything I've ever done. I haven't had that same feeling in the Senate."
He said if his ability to be productive in the Senate is "stopped because of pure, hard-core politics," he would have to make a decision following the 2014 midterm elections. "I will keep all options open," he said.
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