“He gives me hope,” Ms. Husaini said in an interview last month, shortly before she joined the campaign on a fellowship. But she sighed when the conversation turned to his denials of being Muslim, “as if it’s something bad,” she said.

Throughout the primaries, Muslim groups often failed to persuade Mr. Obama’s campaign to at least send a surrogate to speak to voters at their events, said Ms. Ghori, of the Muslim Public Affairs Council.

Before the Virginia primary in February, some of the nation’s leading Muslim organizations nearly canceled an event at a mosque in Sterling because they could not arrange for representatives from any of the major presidential campaigns to attend. At the last minute, they succeeded in wooing surrogates from the Clinton and Obama campaigns by telling each that the other was planning to attend, Mr. Bray said.

American Muslims have experienced a political awakening in the years since Sept. 11, 2001. Before the attacks, Muslim political leadership in the United States was dominated by well-heeled South Asian and Arab immigrants, whose communities account for a majority of the nation’s Muslims. (Another 20 percent are estimated to be African-American.) The number of American Muslims remains in dispute as the Census Bureau does not collect data on religious orientation; most estimates range from 2.35 million to 6 million.

A coalition of immigrant Muslim groups endorsed George W. Bush in his 2000 campaign, only to find themselves ignored by Bush administration officials as their communities were rocked by the carrying out of the USA Patriot Act, the detention and deportation of Muslim immigrants and other security measures after Sept. 11.

As a result, Muslim organizations began mobilizing supporters across the country to register to vote and run for local offices, and political action committees started tracking registered Muslim voters. The character of Muslim political organizations also began to change.

“We moved away from political leadership primarily by doctors, lawyers and elite professionals to real savvy grass-roots operatives,” said Mahdi Bray, executive director of the Muslim American Society Freedom Foundation, a political group in Washington. “We went back to the base.”

In 2006, the Virginia Muslim Political Action Committee arranged for 53 Muslim cabdrivers to skip their shifts at Dulles International Airport in Northern Virginia to transport voters to the polls for the midterm election. Of an estimated 60,000 registered Muslim voters in the state, 86 percent turned out and voted overwhelmingly for Jim Webb, a Democrat running for the Senate who subsequently won the election, according to data collected by the committee.