Maybe it was the kiss that John Boehner planted on Nancy Pelosi's cheek that early January day in front of the entire House of Representatives that should have provided a clue.

Not long afterward, Boehner, the Republican Speaker of the House, dispatched a top healthcare adviser to a secret meeting with his counterpart working for Pelosi, the Democratic leader.

The Boehner aide's mission, according to a source who asked not to be identified, was to determine whether Pelosi might be willing to collaborate on major legislation.

Two months later, after scores of private conversations and hard bargaining, the work by America's political odd couple bore fruit with a 392-37 House vote to overhaul the Medicare program that delivers healthcare for the elderly and disabled, including fixing for good its troubled formula for paying physicians.

Still, the rare example of bipartisan cooperation is unlikely to signal smooth sailing for daunting matters facing Congress in coming months, including a series of fiscal challenges and a major infrastructure bill.

Many of those familiar with the Medicare overhaul negotiation called it a unique circumstance not easily replicated. One House Republican aide said the two leaders caught ‘lightning in a bottle here.’

The Senate and President Barack Obama must still approve the overhaul for it to become law, but Obama has signaled his support and the lopsided House vote is expected to propel its passage through the upper chamber.

The Republican-controlled Congress has struggled to achieve major legislative successes due to Democratic opposition and as Boehner has labored to control his party's ‘Tea Party’ fiscal conservatives. Gridlock over national security funding, and Republican fights over abortion and border security have raised questions over the party's promise to govern effectively.

‘Don’t look now, but we are actually governing,’ said Republican Representative Renee Ellmers after Thursday's vote.

ROCKY BEGINNING

Things got off to a rough start at the initial January meeting of Boehner and Pelosi aides, joined by Republican and Democratic staff from social program oversight committees.

That was the case despite Boehner's emissary signaling a concession at the outset: No longer would Boehner insist that the full, $214 billion cost of the initiative be offset with savings elsewhere, according to the source.

Instead, only part of the cost would have to be paid for, as long as the final product also included long-term structural changes to Medicare that Republicans badly wanted.

In Boehner's favor was widespread support, even among many Republican fiscal hawks, for an end to a string of temporary fixes - 17 times in the last 12 years - that prevented deep cuts in doctor payments that could have strangled Medicare.

Other upcoming bills over borrowing and spending carry far higher national stakes and go to the heart of the fiscal issues that Congress appears ever more divided over.

Pelosi did not let the initiative stall, agreeing to what would become an eight-week struggle for a bill that also ended up containing important Democratic priorities. One, for instance, was a two-year extension of healthcare for children from low-income families and community health centers.

Pelosi's lieutenant, Representative Steny Hoyer, said of the emerging deal, ‘I would like a four-year extension ... we don't have the votes. Two is better than zero.’

As the negotiations neared an end last week and Senate Democratic Leader Harry Reid pressured Pelosi to squeeze more out of Boehner on programs for the poor, and to further scale back Republican anti-abortion language, Pelosi held tough, according to a Senate Democratic leadership aide.

Push too far, she warned Democrats, and Boehner would kill the community health center portion of the deal. And that would likely kill the entire effort.

The San Francisco liberal's performance prompted Boehner to praise her in a closed-door meeting of House Republicans, whose more conservative members view Pelosi as toxic, said a source.

She fought to hold the deal together, in part, to achieve a larger goal, a Senate aide said.

‘Pelosi wanted the deal to create what could become a new dynamic over there and assert her relevance’ in upcoming legislative battles,’ the aide said.

As for the Democrats, they wonder whether Boehner has turned a corner.

‘The difference here is that he came to her first,’ before things devolved into a slugfest, said the House Democratic aide. ‘It's a departure.’