WASHINGTON - The largest U.S. Islamic civil rights group was among the first to congratulate President-Elect Democrat Barack Obama, a man who some opponents tried to portray as a Muslim because of the childhood years he spent in Indonesia.

“President-elect Obama’s victory sends the unmistakable message that America is a nation that offers equal opportunity to people of all backgrounds,” the Council on American Islamic Relations said in a statement just minutes after Obama’s victory speech in Chicago.

Nihad Awad, executive director of the group, said they hoped to offer the Obama administration some support and advice.

“We look forward to having the opportunity to work with the Obama administration in protecting the civil rights of all Americans, projecting an accurate image of America in the Muslim world and playing a positive role in securing our nation,” Awad said.

Obama, who will be the first black U.S. president and whose middle name is Hussein, is a Christian. But throughout the campaign, false rumors circulated on the Internet that he was Muslim and therefore not a suitable candidate for the White House.

Son of a Kenyan father and white American mother, Obama spent part of his childhood in largely Muslim Indonesia.

More than 20 million copies of a film called “Obsession: Radical Islam’s War Against the West” were included as advertising supplements in newspapers across the country, many in battleground states.

CAIR lashed out against the film, which was distributed by a private group unaffiliated with the McCain campaign and featured suicide bombers, children being trained with guns, and a Christian church said to have been defiled by Muslims.

Former Secretary of State Colin Powell, a Republican and African American, endorsed Obama last month saying that he was troubled by the attempts to link Obama to Islam.

“Is there something wrong with being a Muslim in this country?” he asked on NBC’s “Meet the Press.”

“The answer’s no, that’s not America. Is there something wrong with some seven-year-old Muslim-American kid believing that he or she could be president? Yet I have heard senior members of my own party drop the suggestion ‘he’s a Muslim and he might be associated with terrorists.’ This is not the way we should be doing it in America,” Powell said.

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- Photo credit: Reuters/Shannon Stapleton (Obama speaks at his victory rally)