WASHINGTON (Reuters) - The Supreme Court on Monday said it will rule for the first time on one of several tough, new state immigration laws, with a decision coming in the middle of the 2012 presidential election campaign.

Potentially deepening political divisions over the contentious immigration policy issue, the court will decide if key parts of an Arizona crackdown can proceed. The ruling could have implications for similar tough laws adopted recently in other states.

A decision upholding the Arizona law would be a legal and political blow to President Barack Obama, who has criticized it, as he seeks re-election. A pro-Arizona ruling also could encourage other states to pursue equally harsh measures.

The Supreme Court's decision to intervene in the dispute was a setback for the administration, which sued to challenge the law and urged the justices to reject Arizona's appeal.

The law requires police to check the immigration status of anyone they detain and suspect of being in the nation illegally. Other parts require immigrants to carry their papers at all times and ban people without proper documents from soliciting for work in public places.

The justices are likely to hear arguments in the case in April, with a ruling due by July. In addition to the Arizona case, the court will also decide Obama's healthcare overhaul law, putting its 2012 docket squarely on the election agenda.

About 11 million illegal immigrants are believed to be in the United States and immigration is a major political issue, especially in states such as Arizona that border Mexico.

Republican Arizona Governor Jan Brewer, who signed the measure in April 2010, welcomed the court's decision and was confident it will uphold the law.

"Decades of federal inaction and misguided policy have created a dangerous and unacceptable situation, and states deserve clarity from the court in terms of what role they have in fighting illegal immigration," she said in a statement.

OBAMA CONCERNED

Obama and other opponents, including many Democrats and civil rights groups, have criticized the Arizona law and said it could lead to harassment of Hispanic-Americans.

The Obama administration challenged it on the grounds that the federal government has exclusive control over immigration enforcement and federal laws preempt the state law. That is the legal issue that the Supreme Court agreed to decide.

A federal judge and a U.S. appeals courts ruled for the Obama administration and put on hold the disputed provisions.

The law's supporters, including many Republicans, said states need to take aggressive action because the federal government has failed to do enough to stop the flow of illegal immigrants into the country.

Paul Clement, a former solicitor general during the Bush administration who represents Arizona in the Supreme Court appeal, said the case involved an important nationwide issue.

"It is widely recognized that the federal immigration laws are not adequately enforced," he said. "This broken system leaves the people and government of Arizona to bear a disproportionate share of the burden of a national problem."

The Obama administration's top courtroom lawyer, Solicitor General Donald Verrilli, opposed the appeal and said further review of the case by the Supreme Court was unwarranted.

SUPPORT FOR ARIZONA

Eleven other states supported Arizona's appeal, along with 59 members of the U.S. Congress. Congress has been unable to agree on comprehensive new immigration measures.

States with laws similar to Arizona's include South Carolina, Alabama, Utah, Georgia and Indiana.

The Supreme Court in May upheld a different Arizona law that allows the state to shut down businesses that hire illegal immigrants.

The court's conservative majority rejected the argument by business and civil rights groups and by the Obama administration that the 2007 Arizona law conflicted with federal immigration law.

In the new case, Justice Elena Kagan did not take part in considering the appeal. She apparently recused herself because she had been involved in the matter in her previous job as Obama's solicitor general.