* Experts say it’s too soon for broad assessments
* Obama spotlights milestone with trip, news conference
* Big agenda gets boost after key senator switches parties
* Obama says country moving in ‘right direction’ (Adds comment from Specter event, paragraph 8)
By Caren Bohan
WASHINGTON, April 28 (Reuters) - Barack Obama on Wednesday marked the 100th day of his presidency after a whirlwind start in which he has signaled a new approach on policies from the economy to climate change to U.S. relations with Iran.
Some have used the milestone to assess Obama’s policies, even as analysts cautioned it was too soon to say whether his long list of initiatives will yield success.
Underscoring the challenge Obama still faces in pulling the country out of recession, new government data showed the economy contracted at 6.1 percent in the first quarter, a steeper-than-expected pace, as exports sharply declined.
While dismissing the 100-day milestone as an artificial gauge created by the media, the White House is nonetheless putting a spotlight on it with high-profile events.
Those include a visit by Obama to Arnold, Missouri, near St. Louis, for a town hall event at 11:20 a.m. EDT (1520 GMT) and a televised news conference at the White House at 8 p.m. EDT/0000 GMT.
The popular president, whose approval ratings are above 60 percent, will likely use the events to push his agenda for overhauling health care, fixing the troubled banking sector, rescuing U.S. automobile companies, combating global warming and pursuing greater engagement abroad.
Looming large as well for Obama is a flu outbreak that has presented him with his first public health emergency and a simmering controversy over his decision to release classified documents detailing harsh interrogations of terrorism suspects during the Bush administration.
Giving a boost to Obama’s domestic agenda was the decision this week by Pennsylvania Senator Arlen Specter to leave the Republican Party and join the president’s Democrats.
Specter’s move may put Obama’s party within reach of a crucial 60-seat majority in the Senate. That could make it easier for Obama to pass some of his top initiatives, such as health care reform.
Appearing with Specter at the White House just before flying to Missouri, Obama said, "In these 100 days we have begun to move this nation in the right direction."
The tradition of marking the first 100 days of U.S. presidencies dates back to Franklin Delano Roosevelt, who trumpeted his ability to push through 15 pieces of major legislation in that time period after taking office in 1933 in the midst of the Great Depression.
"There is no magic to the first 100 days," said Ross Baker, a political science professor at Rutgers University in New Jersey. "I think people are always looking for a marker or some sort of guidepost."
As an example of the measures’s flaws as a leading indicator, many analysts cite the first 100 days of the presidency of Obama’s predecessor, George W. Bush.
The Republican president’s two terms in office came to be defined by decisions such as the launch of the Iraq war that occurred in the aftermath of the Sept. 11, 2001, attacks -- nearly nine months after Bush took office.
Still, Baker and other experts said Obama’s early months have revealed much about his style of governing, including his calm demeanor and effectiveness at commanding the stage but also his penchant for piling a lot onto his policy plate.
So far in his presidency, Obama has enacted a $787 billion stimulus program, launched a drive to overhaul the health care system, made overtures toward longtime U.S. foes Iran and Cuba and unveiled new strategies for the Iraq and Afghanistan wars.
William Galston, a scholar at the Brookings Institution and a former adviser to President Bill Clinton, said he viewed the 100-day mark as "an entirely artificial benchmark."
On the other hand, Galston said, "I think we’ve learned a fair amount about Obama the human being occupying the Oval Office.
"But a lot of people are leaping from the fact that he’s set an enormous number of things in motion to the conclusion that those things that are now in motion are necessarily going to reach the finish line," Galston said. "It’s not a leap I‘m prepared to take."
On the domestic policy side, Obama has been criticized by some who contend the stimulus package and a proposed $3.55 trillion budget he laid out for 2010 will curb economic growth in the future by leading to a pileup of government debt.
Some critics have also faulted Obama’s handling of the banking crisis, saying he should have moved earlier and more aggressively to try to grapple with problem of bad debt hanging over the financial system.
But Obama’s supporters point to what they see as early signs his economic remedies may be working, including a steadier tone to the stock market and a stabilization of new claims for jobless benefits after their prior huge increases.
(Editing by Will Dunham)
(For a summary of Obama’s economic plans, click here [nN25470233])
(For a rundown of Obama’s major campaign promises, click here [nN24436844])
(For more information about Obama’s foreign policy challenges, click here [nN28337591])