Sen. Scott Brown (R-Mass.) speaks during a news conference at the U.S. Capitol in February. (Win McNamee/GETTY IMAGES)

Fresh off his monthly National Guard duty, Sen. Scott Brown (R-Mass.) returned to Washington Tuesday and said he isn’t ruling out a return to politics despite losing last week to Democrat Elizabeth Warren.

Since losing his Senate seat, Brown’s name has been mentioned as a possible candidate to succeed Sen. John F. Kerry (D-Mass.) if the Bay State’s senior senator is tapped by President Obama to lead the State Department or Pentagon. Others believe that Brown may prefer to run for governor of Massachusetts in 2014, noting that the state has a track record of electing other moderate Republicans as chief executives.

“I have a job to do right now and there is not an opening for governor, nor is there an opening for senator,” he said when asked by reporters Tuesday afternoon. “But there is an opening for a dad and a husband and that’s the role I want to play.”

Still sounding like a candidate, Brown said he hopes the Senate is able to wrap up debate on the impending “fiscal cliff” and other remaining issues during the lame-duck session.

“The American people are demanding — regardless of the outcome of the election, one common theme we heard from both sides is that they’re tired of the gridlock and they’re tired of the lack of cooperation,” he said. “And I was hopeful when I heard Sen.-elect Warren say that she plans to be working in a bipartisan manner to solve those problems. So I’m hopeful that you’ll give her the same scrutiny that you gave me over the last two and a half years.”

Brown said he hasn’t spoken yet with Warren, who visited the U.S. Capitol Tuesday for new senator orientation sessions, but promised the transition will be as seamless as possible.

Asked about how the Republican Party needs to adapt to the nation’s shifting demographics, Brown bemoaned the loss of moderate voices in the Senate — and signaled that he’s eager to help the party rebuild.

“We need to be a larger tent party,” he said. “I’m a pro-choice, moderate Republican. There’s a vanishing breed here, and you know that now. You’ve lost Joe Lieberman, Richard Lugar, Kent Conrad, me, Olympia Snowe. That group in the middle is vanishing. And there are on both sides extremes, as you all know, kind of pushing back against the middle. I’ve always felt that that group in the middle is quite frankly the most powerful group because they have the ability to get to that 60-vote threshold and get things done. So I’m hopeful that we’ll be a more tolerant, open-minded party. And I hope to be able to continue playing a role, but I don’t know what yet.”

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