* Top officials have cited options in the past
* Analysts see vulnerabilities for Obama's base
* Any action unlikely until after November vote (Adds quotes, details and background)
By David Morgan and Jeff Mason
WASHINGTON, March 28 The White House said on Wednesday that it was not working on contingency plans for President Barack Obama's signature healthcare law, in the event that the Supreme Court struck down all or part of the sweeping reforms.
After three days of landmark Supreme Court hearings that raised doubts about the law's fate, White House spokesman Josh Earnest said the administration remains confident that the 2010 reform measure would be upheld when justices issue their ruling toward the end of June.
"There is no contingency plan that's in place. We're focused on implementing the law," Earnest told reporters. "If there's a reason or a need for us to consider some contingencies down the line, then we'll do it then."
A negative ruling from the court would be seen as a major blow to Obama in the middle of an election year, when Republicans are demanding the repeal of the Patient Protection and Affordable Care Act.
Obama's re-election prospects already face substantial challenges. A new Reuters/Ipsos poll shows that two-thirds of Americans, including a majority of Democrats, disapprove of his performance on another big issue: high gas prices.
The healthcare law and its unpopular individual mandate, which requires most Americans to have health coverage beginning in 2014, came under sharp scrutiny from the high court's five conservative justices.
Doubts about its future deepened with tough courtroom questioning about whether the mandate exceeds the government's constitutional authority.
Reform advocates contend that the mandate is vital to the law's main objective of extending healthcare coverage to more than 30 million uninsured Americans.
"VARIETY OF STRATEGIES"
Administration officials have spoken openly about possible contingencies in the past.
At a Reuters Health Summit last May, Health and Human Services Secretary Kathleen Sebelius said there would be a number of ways to expand health coverage if the mandate were overturned.
"There are all kinds of sign-up possibilities, auto enrollment and a variety of strategies," she said.
But analysts say the week's proceedings may have left Obama in too fragile a position to speak publicly about contingencies.
The White House could undermine his political base by openly preparing for defeat, particularly on the mandate, which is interwoven with popular consumer protections including a measure guaranteeing healthcare access for people with pre-existing conditions.
"They can't risk having the president look like he's folding, or giving up, or anything like that," said Joseph Antos of the conservative American Enterprise Institute.
If the court struck down the law or its main provisions, analysts say the White House would likely postpone any decision on how to move forward until after the Nov. 6 general election.
They add that the loss of the mandate alone could leave the healthcare law at the mercy of congressional gridlock months after the election and raise doubts about the administration's ability to usher key reforms into place by a Jan. 1, 2014, deadline. (Editing by Xavier Briand)