UPDATE 1-Obama Healthcare Law Headed for U.S. Supreme Court

* Appeals courts have issued conflicting rulings

* Supreme Court ruling expected before 2012 elections

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By James Vicini

WASHINGTON (Reuters) - The Obama administration Monday cleared the way for the Supreme Court to decide in its 2011-12 term the president's signature healthcare law that requires Americans to buy insurance or face a penalty.

A Justice Department spokeswoman said it decided against asking the full U.S. Appeals Court for the 11th Circuit to review the August ruling by a three-judge panel of the court that found the requirement unconstitutional.

The decision not to seek review by the full appeals court will likely speed up consideration of the matter by the high court in its 2011-12 term that begins next week. A ruling could come by late June, in the middle of the presidential campaign.

The Supreme Court has long been expected to have the final word on the legality of the individual mandate, a cornerstone of President Barack Obama's healthcare law. A big uncertainty has been over when the court would decide the issue.

The law's fate before the nine-member court, closely divided with a conservative majority and four liberals, could come down to two Republican appointees, Chief Justice John Roberts and Justice Anthony Kennedy, legal experts have said.

The law, adopted by Congress in 2010 after a bruising battle, is expected to be a major political issue in the 2012 elections as Obama seeks another four-year term. All the major Republican presidential candidates oppose it.

Obama, a Democrat, has championed the individual mandate as a major accomplishment of his presidency and as a way to try to slow soaring healthcare costs while expanding coverage to the more than 30 million Americans without it.

The 11th Circuit appeals court, based in Atlanta, ruled by a 2-1 vote last month in favor of 26 states and others who challenged the mandate for exceeding the power of Congress.

The Obama administration could have asked the full U.S. 11th Circuit Court of Appeals to reconsider its decision. But that could have pushed back any Supreme Court ruling to its 2012-13 term.

The 2-1 ruling ruling conflicted with other appeals courts that have upheld the law or have rejected legal challenges, including a lawsuit by the state of Virginia which was dismissed on procedural grounds.

A U.S. appeals court based in Cincinnati ruled Congress had the power to adopt the individual mandate, which takes effect in 2014. The losing side in that case, the Thomas More Law Center, already appealed to the Supreme Court in July.

The administration has steadfastly maintained its belief that the law will survive judicial scrutiny and be upheld by the Supreme Court. The states that have challenged the law have argued it went beyond Congress' authority to require coverage. (Additional reporting by Jeremy Pelofsky; Editing by Doina Chiacu and Eric Walsh)