Barack Obama has used his first 100 days in office to set a foundation for the rest of his presidency. Time will be the judge of how successful his early months have been in resolving major U.S. challenges.

Obama, whose move into the White House came with high expectations, has given hope to Americans that better days lie ahead, showing himself in command of the issues and displaying an easy-going maturity that many might not have expected from the 47-year-old.

His supporters are ecstatic about him.

I think what's happened with President Obama is, as in the elections, a lot of people underestimate ... the man who I believe is a great leader, Democratic Representative Elijah Cummings told MSNBC.

At the same time, Obama has been unable to bridge the partisan divide that often consumes Washington.

When tough decisions have been made, time and again he has sided with fellow Democrats who control Congress, leading opposition Republicans to believe his view of bipartisanship is when they align themselves with his views.

We believe over the last three months we've offered a lot of better solutions than what has been proposed by the administration, said John Boehner, the top Republican in the House of Representatives. Unfortunately, they've decided to go it alone, on a partisan basis, over these last three months.

In a whirlwind of activity, Obama has devoted the period since his historic inauguration on January 20 as the first black U.S. president to trying to resuscitate the economy and fix the financial crisis at the heart of the global downturn.

He gained speedy congressional approval of a $787 billion stimulus plan whose full impact on the economy remains to be felt. He won an early battle in his bid for a $3.55 trillion budget for fiscal 2010, shocking deficit hawks because it would generate a deficit of more than $1 trillion.

On trips to Europe and Latin America, he has attempted to soften America's image from the perceived lecturing tone of the Bush administration, telling Europeans he wanted to listen to their views and, at a Latin American summit, shaking the hand of Venezuela's anti-American president, Hugo Chavez.

What we can see is that he has set a new tone and gotten some significant things done, said Larry Sabato, a political science professor at the University of Virginia. But what the first 100 days doesn't do is predict the course of the rest of his presidency.

ARTIFICIAL BENCHMARK

A president's first 100 days are in many ways an artificial benchmark. But it is a time when he has the best chance to use the influence and political capital gained from his election victory.

Rejecting criticism he was trying to do too many things at once, Obama has begun efforts to overhaul the U.S. healthcare system, tackle global warming and improve education, arguing they are part and parcel to ending the recession.

His potential for success in the future beyond the 100 days is going to depend very heavily on the success of what he has been able to get done in the first 100 days, said David Rohde, a political science professor at Duke University.

Franklin Roosevelt set the standard for a president's first 100 days in 1933 by putting in place the building blocks of his New Deal programs to pull the United States out of the Great Depression.

Other presidents have also had successful starts to their terms -- think of Lyndon Johnson launching his Great Society or Ronald Reagan pushing his less government, less taxes approach.

Obama's unpopular Republican predecessor, George W. Bush, won major tax cuts despite limping into office in 2001 after a bitter Florida recount battle with Democrat Al Gore.

What has distinguished Obama's first 100 days has been his attempt to tackle not just the U.S. recession but a number of other major problems.

If I had to pick one word that described his 100 days, it would be 'creative,' said presidential scholar Stephen Hess, a professor at George Washington University. It hasn't been quite like any other 100 days. He's really tried to do an incredible amount of things.

The public has given Obama room to maneuver.

The Gallup polling organization said he had averaged a solid 63 percent approval rating throughout this period.

Andrew Kohut, director of the Pew Research Center, said Obama and Republican icon Reagan have much in common, in that they were personally far more popular than their agendas.

His approval ratings remain high even as he proposes a dramatic new approach to the role of government that has many doubters, Kohut said.