Sen. Mark R. Warner walks the halls of the Capitol these days with a surprising spring in his step for someone whose party just lost control of the Senate.

“Congratulations!” Sen. Lindsey O. Graham (R-S.C.) said to the Virginia Democrat as they passed in a corridor, a reference to Warner’s narrow victory in his reelection bid. Warner said he had missed Graham at a party the night before for another Republican, Sen. Saxby Chambliss. “Not a lot of Democrats there,” Warner joked.

Warner has lost many of his moderate Democratic allies, including the rest of the “Mark caucus” — Mark Begich of Alaska, Mark Pryor of Arkansas, Mark Udall of Colorado. Some of his closest Republican friends he made from failed attempts at major financial reform — Oklahoma’s Tom Coburn and Georgia’s Chambliss — are retiring.

But the new Republican Congress will offer him certain advantages. In six years, Warner has moved up from last in seniority to 59th. He is also one of the few centrist Democrats left, one of a handful who refused to support Sen. Harry M. Reid (D-Nev.) as minority leader.

“I think Mark, he’s going to have a little more fun in this next Congress even though he’s in the minority,” Chambliss said. “Because he’s a guy that wants to get things done.”

A blue Virginia tide turns red for 2014

Instead of trying to win over more liberal Democrats to get his bills to the floor, Warner probably will be courted by Republicans looking for enough votes to overcome a filibuster. During the most successful years of his political career — his four years in the Virginia governor’s mansion — he dealt with a legislature controlled by Republicans.

“This election reenergized me,” Warner said in a recent interview between a series of the kind of nomination votes he ridiculed on the campaign trail as an example of Washington’s inability to accomplish anything significant. “There’s going to be a different framework now,” he said, “and in many ways, for somebody kind of in the middle who’s about building bipartisan coalitions, there may even be more opportunities for me. . . . I’m looking forward to that.”

Warner has said repeatedly that making connections with the other party is an explicit goal, and he has promised to put forward a major bill only if a Republican co-sponsors it.

“I really think he’s going to be in a unique spot in terms of the ability to try to move forward good policy,” said Sen. Timothy M. Kaine (D), Virginia’s junior senator. “This is a real relationship place. They’re going look at who, when they were in a majority, came to them.”

On this morning, though, Warner was working with liberal hero Sen. Elizabeth Warren (D-Mass.) on housing-finance reform. The two got to know each other during intense negotiations over a bill Warner wrote with Sen. Bob Corker (R-Tenn.), although Warren ultimately decided not to back that compromise because she thought it lacked sufficient protections to ensure access to mortgages for middle-income Americans. Without enough support from progressives, the bill did not get a floor vote.

On Wednesday, Warner and Warren were grilling Mel Watt, director of the Federal Housing Finance Agency, over smaller fixes that could be accomplished without Congress.

“When the financial crisis happened, a lot of the mortgage insurers weren’t there,” Warner said, sharing a glance with Warren, who nodded and smiled. When it was her turn to speak, Warren used more emotional terms: “People are continuing to lose their homes every day.”

The housing-finance issue, a complicated problem left unsolved after the financial crisis, is emblematic of the possibilities for Warner but also the potential disappointments. Sen. Richard C. Shelby (R-Ala.), for instance, (who is expected to take over as chairman of the Senate Banking Committee next year) voted against the compromise bill that Warner helped craft because he thought it left in place too big a government role in the mortgage business.

In other words, the centrist policies Warner wants to pass may fare no better in a Republican Senate than in a Democratic one.

Warner has never had a huge following on the left.

“It’s not as if Warner’s ‘radical centrism’ b.s. guarantees him reelection anymore anyway,” liberal Virginia blogger Lowell Feld wrote after the senator’s vote in favor of the Keystone XL pipeline last week. “So why put up with Warner’s Republican Lite garbage anymore?”

Warner has resisted the notion that he should have spent more time in Northern Virginia in the most recent campaign or spoken more strongly on issues backed by the Democratic base. “I’m not going to change who I am,” he said. But after several rocky years, Warner has developed a better relationship with Democratic leadership, forged in part during the government shutdown. He won a long-coveted seat on the Senate Finance Committee this year, though he may lose it when Republicans take over.

“It’s different being a legislator. You have to build the trust and the goodwill; you have to show that you’re going to be serious about the details,” he said.

“I think Mark has moved into his areas of expertise — finance, the financial sector,” said Kaine, himself a former Virginia governor. “What you learn over time is that, okay, it’s not an executive job, but it is an expertise job, and expertise jobs can be really fun and important and challenging.”

And Warner hopes that his assiduously cultivated Republican ties will pay off.

From the committee hearing, Warner headed to lunch with the Virginia Chamber of Commerce, where lawmakers mingled with lobbyists from Appalachian Power Co. and Capital One. Rep.-elect Dave Brat (R-Va.), a conservative economics professor who toppled former House majority leader Eric Cantor in the primary this year, nodded as Warner made his familiar pitch for a “grand bargain” on entitlements and the deficit.

In one of his trademark jokes that managed to sound self-deprecating while reminding listeners of his extraordinary success, Warner said that only with “trepidation” would he make a prediction about technology: The last time he did so he was told cellphones would never be used widely. “They were wrong; I got rich.”

Warner’s new obsession: unmanned aircraft systems, better known as drones. “Virginia ought to be the center of excellence on building, designing, constructing what could be . . . revolutionary,” he said. On his way out, lobbyists from Richmond-based McGuireWoods stopped him to make sure they got a photograph. Rep. Rob Wittman, a Republican from Virginia’s 1st Congressional District, pulled him aside to ask about a bill regarding Chesapeake Bay restoration that is set to pass during the lame-duck session.

“Some of the other state delegations can’t sit in a room together,” Wittman said. “We’re all focused on the proper ends for Virginia.”

Later, after an intelligence briefing and a private meeting to discuss the 2024 Olympics, Warner headed to the Russell Rotunda to shoot a CNN interview with Sen. Kelly Ayotte (R-N.H.) about another successful piece of legislation, a bill that eliminates several dozen unnecessary federal reports. The network threatened to cancel the interview unless the senators agreed first to answer a question about President Obama’s executive action on immigration. While Ayotte said she does not “think that it’ll poison the well” for any cooperation with the president, many more-conservative lawmakers think otherwise.

“No more questions?” Warner asked, offering to name 14 government programs that the Office of Management and Budget, with bipartisan agreement, suggested eliminating. The producers just smiled.