New York ? The nation’s first African-American president addressed the nation’s oldest civil rights organization at its 100th anniversary convention in Manhattan on Thursday night at the Hilton New York, telling a packed and cheering crowd his election was made possible by the organization’s history of successes and the courage of its leaders.

“Because of them I stand here tonight, on the shoulders of giants,” Obama said. “And I’m here to say thank you to those pioneers and thank you to the NAACP.”

He said despite their efforts, racial and social barriers continue to prevent America from tapping the potential of its people.

During a nearly 40-minute speech, the former Illinois senator told members of the predominantly black civil rights group that social ills that have limited the achievements of many black Americans also hamper other groups, notably Hispanics and poor white Americans.

Alluding to the recession, Obama likened the economy to one built on sand, and said a new foundation for growth and prosperity was needed to improve the lot “not just of black Americans, but all Americans.”

Obama said a “first rate” education was the right of all Americans, and promised to make the United States the leader in granting college degrees by 2020.

“We want everybody to participate in the American dream,” Obama said. “That is what the NAACP is all about.”

The president’s talk was received enthusiastically by the crowd, which filled the 2,000-seat ballroom and spilled into overflow rooms.

“Oh, man, this was one of the highlights of my life, to be in that room and hear him say he is where he is today because of the NAACP,” said the Rev. Roderick Pearson, president of Long Island’s Islip Town chapter of the NAACP. “It’s a great night for us.”

Dolores Thompson, president of the Huntington (N.Y.) NAACP, said she approved of the president’s willingness to stress self-help in the black community.

“We have to get off our duff,” said Thompson, who has been a community activist since the 1960s. “We can’t expect him to do for us if we won’t do for ourselves. I think that is what he was trying to tell us.”

Obama’s appearance came as sharp racial disparities continue to hamper the nation’s black communities. Obama alluded to recent data showing a widening joblessness gap in New York City that’s pushing blacks further behind whites. He mentioned that blacks are more likely to attend substandard schools, be unemployed or face criminal prosecution than are white Americans.

Obama said his efforts to improve education, health care and the economy for all Americans will lift the black community.

NAACP president Benjamin Jealous said despite the pride of the organization’s members that a black man occupies the White House, the NAACP will press Obama to address America’s racial disparities.