"It’s been a long time coming. But tonight, because of what we did on this day, in this election, at this defining moment, change has come to America," he said in front of a crowd of 65,000 people.

He continued: "All of those watching tonight from beyond our shores, in the parliament and in the palaces, those huddled around radios in the forgotten corners of the world, our stories are singular but our destiny is shared."

"A new dawn of American leadership is at hand," he said to applause.

"To those who would tear the world down, we will defeat you. To those who seek peace and security, we support you."

"We have proved that the true strength of our nation comes not from the scale of our wealth but from the power of our ideals — opportunity, democracy, liberty and hope."

He paid tribute to his campaign team, his wife, children and recently deceased grandmother.

"Along with the family that made me who I am. I miss them tonight. I know that my debt to them is beyond measure," he said.

He added: "I was never the likeliest candidate for this office. We didn’t start with much money or many endorsements."

"Our campaign was not hatched in the halls of Washington. It began in the backyards of Des Moines and the living rooms and the front porches of Charleston.

First black president

Americans emphatically elected Democrat Barack Obama as their first black president Tuesday, in a transformational election which will reshape US politics and the US role on the world stage.

Obama, 47, will be inaugurated the 44th US president on January 20, 2009, and inherit an economy mired in the worst financial crisis since the 1930s, two wars in Afghanistan and Iraq and a nuclear showdown with Iran.

Television networks projected his victory over Republican John McCain after Senator Obama solidified traditional Democratic states and cut deep into the Republican territory which his rival needed to control to win the White House.

Obama’s win was greeted with euphoria by a vast crowd gathered in his home city of Chicago, as his supporters, screamed, waved American flags as they waited for him to arrive to deliver his victory speech.

New York’s Times Square exploded in joy at a moment of healing for America’s racial scars, a huge crowd gathered outside the White House and the result immediately reverberated around the world.

Democrats also made ground in Congress, and will hold an unshakeable monopoly in power in Washington after a rare generational and political realignment.

McCain concedes defeat

McCain was gracious in defeat, and noted that his election was a moment to cherish for African Americans.

"The American people have spoken, and they have spoken clearly. A little while ago, I had the honor of calling Senator Barack Obama to congratulate him on being elected the next president of the country that we both love," he said.

"Though we fell short, the failure is mine, not yours," he told a crowd of supporters in Phoenix in his home state of Arizona.

President George W. Bush who has steered his country through eight turbulent years also congratulated Obama.

"Mr president-elect, congratulations to you," White House spokeswoman Dana Perino quoted the president as saying in a phone call to Obama.

"What an awesome night for you, your family and your supporters. Laura and I called to congratulate you and your good bride."