A month ago President Obama was the big loser of 2010, the leader whose party had given up historic losses in the House and who was facing questions about his future. On Friday, with the stroke of his pen on a compromise tax bill, he reminded his adversaries of the essential resilience of the occupant of the Oval Office.

Whether the compromise proves to be a fleeting moment of bipartisanship or the beginning of a genuine turnaround in Obama's political fortunes won't be known until well into next year. But if the president can find the formula that allows him to deal when he can and fight when he must, then his prospects for true revival could dramatically improve.

What seems clear is that Obama has begun to position himself back on more comfortable ground in the wake of the self-described shellacking he took in the midterm elections. By instinct and demeanor, he is a politician who prefers finding common ground with his opponents. At a moment of political weakness, the tax package provided him the vehicle to quickly reassert that part of his political personality at a time when he needed the public to take a fresh look at him.

The deal is also a reminder that, despite unrest in his party's base over the terms of the agreement, the Obama White House recognizes that the 2012 election will be won or lost with independent voters, who prize results and prefer to see Republicans and Democrats working constructively. Virtually every political calculation Obama makes over the coming months will be with that compass in hand.

The bill that Obama signed Friday comes at a cost. It virtually guarantees that he will not fulfill during his first term one of the major promises of his 2008 campaign, which was to roll back the income tax rates for the wealthiest Americans. That rankles many liberal activists in the Democratic Party who believe Obama should have fought harder before yielding on that issue.

The president also unnecessarily disparaged both left and right as he defended the agreement in the days after it was first announced. He described liberal opponents of such deals as "sanctimonious" and purists, while likening the Republicans with whom he made the deal to "hostage takers" for holding out to extend tax cuts for the wealthy along with the middle class.

The tax fight widened the divide between the president and many House Democrats and their liberal allies in the party's activist base. Given the election results and now a tax deal in which they were left as bystanders to the negotiations, House Democrats are in an understandably surly mood, fearful that Obama will ignore them in the future to further his own political well-being.

The absence of most Democratic congressional leaders from the White House signing ceremony spoke loudly of that rift. Left untreated, that could become a serious political problem for the president. If Congress successfully repeals the "don't ask, don't tell" policy on its way out of town, that will go a step in the direction of patching things up - but only one step.

John Feehery, a Republican strategist and former senior House aide, said Obama cannot alienate his base repeatedly without risking a primary opponent in 2012.

"It is quite obvious that he showed some political ruthlessness here," Feehery said in an e-mail. "He cares little about the concerns of House Democrats. If they stand in his way, he will trample over them at the drop of a hat. While that might be politically expedient now, it could prove to be his downfall should he need them later on in his presidency."

For now, however, whatever unrest there is within the House Democratic caucus or among some liberal activists, Obama is not suffering significantly among self-described liberals because of the tax deal. In fact, the agreement enjoys widespread approval.

The latest Washington Post-ABC News poll showed almost identical support among liberals, moderates and conservatives. At least two out of three in all groups said they endorsed the package as negotiated by the White House and congressional Republican leaders.