Senate Majority Leader Sen. Harry Reid, D-Nev., talks Wednesday with The Associated Press in his office on Capitol Hill in Washington.

Washington ? This is the story of a “lame duck” Congress that wasn’t.

Shaken by a historic election in which angry voters canceled Democratic control of the House, lawmakers of both parties and President Barack Obama tried something new: They consulted each other. They cooperated. And finally, they compromised.

From tax cuts to a nuclear arms treaty and the repeal of the ban on openly serving gay soldiers, Congress and the Obama White House closed up their respective shops and headed out for the holidays with an uncommonly full bag of accomplishments.

Bipartisanship was one of them.

“That progress is … a reflection of the message the voters sent in November, a message that said it’s time to find common ground on challenges facing our country,” Obama told reporters before joining his family in Hawaii. “It’s a message that I will take to heart in the new year, and I hope my Democratic and Republican friends will do the same.”

That’s less likely come January, when Republicans take control of the House, gain seats in the Senate and are guided in part by a shrewd GOP leader who has declared that his top priority is denying the president a second term in 2012.

But even he — Kentucky Sen. Mitch McConnell — walks away having had a seat for the first time at the negotiating table with the Obama administration. Technically, he negotiated with Vice President Joe Biden, McConnell’s Senate colleague for years, on a huge package of tax cuts, plus extended benefits for millions of unemployed workers.

Both sides hoped the compromise would win points for pragmatism with centrist and independent voters who will be pivotal in the 2012 elections.

In truth, giving struggling voters an $858 billion Christmas gift was a political no-brainer. But the compromise produced a deal and a visual that would have been hard to imagine only a few weeks earlier.

There was the stern-faced McConnell at Obama’s elbow as the president signed the tax cut deal into law. Absent were the leaders of Obama’s own party — House Speaker Nancy Pelosi and Senate Majority Leader Harry Reid — as well as the gleeful exhortations of bill signings-past.

“I wasn’t going to go to my caucus and tell them that I was part of a deal that we were giving tax cuts to people making more than $1 million a year,” Reid said in an interview late Wednesday, adding that he had excused himself from those negotiations.

In some ways, the tax cuts were as big a deal as Obama’s signature health care overhaul. But this time, Biden mostly stuck to his script — without using an expletive this time. The president spoke, signed the legislation and rose to pat McConnell on the shoulder, giving the country a glimpse of how bipartisan compromise looks and sounds in the Obama era — somber, tightly choreographed and uncomfortable.

It was the first real evidence that the election results had shifted the workflow in Washington. The tax cut deal also may have marked a rebound for a president emerging from the “shellacking” of one Election Day into the last half of his term and his own re-election campaign.

There was more.

The Senate on Dec. 18 joined the House in voting to repeal the military’s “don’t ask-don’t tell” policy against openly gay personnel. The repeal pleased liberals who had been left on the sidelines with the tax cut deal, and it won support among rank-and-file Republicans.

And finally, the Senate on Wednesday ratified the New START nuclear arms treaty with Russia, 71-26. This time, McConnell and his second-in-command, Republican Whip Jon Kyl of Arizona, were left out of the deal-making as Obama, Reid and Foreign Relations Committee Chairman John Kerry, D-Mass., negotiated with like-minded Republicans.

Reid later said the ratification solidified Obama’s standing as a world leader and Nobel Peace Prize winner.

The treaty, he told The Associated Press, was about the standing of the United States in the world community “and whether Barack Obama was a man who deserved the Nobel Peace Prize, a man who has so turned around American foreign policy.”

At the time, some had complained that Obama, less than a year into his presidency, had won the prize prematurely.