Obama has shaped his White House to reflect this syncretic outlook — appointing senior counselors with broad portfolios and five prominent “czars” whose jurisdictions range across those of several departments. And when several of his first round of top-tier nominees stalled in the Senate, the president seemed content to have the West Wing serve as the de facto government — even if that led to a marginalizing of his Cabinet. The administration is already pursuing a sweeping overhaul of the health system without a secretary of Health and Human Services. Much of the direction is coming instead from the head of the White House budget director, Peter R. Orszag , an economist who has Obama’s ear and possesses a thorough knowledge of health costs.

The penchant for tightly concentrated executive-branch clout is in line with recent trends in the American presidency. “There’s been a fear of delegating too much to agencies that started during the conservative revolution and intensified after Hurricane Katrina,” said Julian E. Zelizer, a political historian at Princeton University. “Like his immediate predecessors, Obama wants decision-making focused on his inner circle. If he’s successful, he won’t change this pattern.”

Change Starts from the Top Down

During the transition, Obama said he’d be the one giving his administration thrust and direction. But it was unclear how much his concept of the presidency would be changed by his actual exposure to the job.

The past three months have shown that Obama is supremely confident in his ability to parse recommendations from his advisers, and to be “the decider,” as George W. Bush famously put it. His intelligent and intense chief of staff, Rahm Emanuel , has helped Obama focus on the big decisions, establish clear lines of authority, balance a collection of big egos and ensure that dissenters in the White House get to state their case.

“Obama’s confidence in himself as a leader is at least as great as his campaign led us to believe,” said Brookings’ Galston.

For evidence, look no further than Obama’s April 14 speech at Georgetown University, which broke no new ground but conveyed in a tone of unswerving firmness that any recovery is predicated on building a new foundation for the U.S. economy and changing the political landscape.

Crisis Can Justify Sweeping Action

Obama came to office facing the worst economic crisis in six decades, and on the heels of a highly unpopular predecessor. He’s wagered that the depth and complexity of the recession — particularly the way it touches banking, housing, consumer lending and other aspects of everyday life — have left public opinion malleable and highly responsive to bold leadership.

So far, that bet appears to be paying off. Even though many Americans are ambivalent about some elements of Obama’s recovery plan, such as having the government pay lenders to reduce the monthly payments of homeowners who are at risk of defaulting on their mortgages, a large majority believe he is doing everything he can to stop the slide. A survey of 1,507 adults released last week by the Pew Research Center for the People & the Press found that while only 30 percent of self-identified Republicans support Obama’s agenda, 46 percent have a favorable opinion of the president personally.

The risky side of this bet is that the new president could be reading negative public opinion of Bush as an affirmation of his own boldest goals. If so, he will have to recalibrate some the policy changes he takes on.

Critical to that assessment is how independent voters view the president’s expensive up-front social engineering and efforts to revive the economy. Experts say this group’s patience with Obama could be short-lived if bailouts of automakers and the financial industry fail to bear fruit — or at least produce the sense that the economy is improving.

“There is a concern about overspending, and Republicans are trying to tap it, because they have to use whatever arrows are in their quiver,” said Karlyn H. Bowman, a senior fellow and public opinion expert at the conservative American Enterprise Institute.

The Pew Center’s associate director, Carroll J. Doherty, sees parallels between that potential downside to Obama’s agenda and the trajectory of Ronald Reagan’s first year in office, when unemployment rose from 7.5 percent to 8.3 percent. Though Reagan enjoyed a rosy honeymoon, by the fall of 1981 most Americans lost faith in his economic policies sending the president’s popularity ratings on a long and sustained slide.

“There are some signs independents are getting nervous,” Doherty said. “That is where his popularity has a chance of softening. He has no difficulties with the Democratic base.”

Talent Will Win Out

Obama has surrounded himself with a collection of accomplished advisers, many with Ivy League credentials and experience in the Clinton administration. Comparisons with Kennedy’s “Best and the Brightest” are inevitable, but not just because of the collective brainpower and forceful personalities crammed into the West Wing.

Administration insiders and scholars say Obama, like Kennedy, appears less concerned with rank and position than some of his predecessors and has adopted an informal approach to gathering input. He insists on hearing from everyone in the room, to make sure he is not rendering decisions in a bubble. The approach sometimes conveys a sense of fluidity or even disorder within the White House.

“Obama’s campaign was idealistic and firmly rooted and made you lose sight of the fact he’s pragmatic and not stuck on one way to reach his objectives,” said Princeton’s Zelizer. “At times, he seems torn between what to do, and on foreign policy you see his approach is to feel his way around. But he’s not allowing advisers to dictate what he does at this point.”

But by relying on himself as the ultimate filter, Obama invites speculation about whether he can withstand the crush of daily business and continue to find the time to pore over memorandums and briefing books and think before he acts. White House veterans such as Galston say the temptation to defer agenda items will become acute if Obama encounters a political crisis at home — say, Democrats splintering over his health care proposal — or gets embroiled in a prolonged foreign policy crisis.

Spiva, who worked at the Harvard Law Review when Obama was its editor, believes that the president’s self-discipline and ability to project a sense of control have already helped him weather the brunt of the financial crisis. “I’ve never truly seen him get rattled by anything,” he said. “I’m sure Democrats will fragment over big votes like they always do, and he may not get some things through Congress, but I just don’t see him panicking.”

Galston sees a great deal of self-control taking shape in Obama’s presidency, as well — noting that he keeps juggling the agenda he campaigned to introduce, while also incorporating more ad hoc challenges, great and small. “The combination of extraordinary circumstances and the skills and experience he brings to the job are giving him an opportunity to get beyond what he calls the stale arguments and entrenched positions that have limited political possibilities over the past decade,” Galston said.