While handily taking the New England states, Obama gained the lead in the race by also winning the hotly contested Ohio and Pennsylvania.
The Western states helped put him firmly in the victory column, and the announcement that he had the necessary electoral-college votes was made immediately after the polls closed in California at 11 p.m. ET.
Though race was a theme that wafted throughout a tough fight against Republicans John McCain and Sarah Palin, most political pundits credited the poor economy as the central factor in the minds of Americans once they closed the curtains in polling booths.
In his concession speech, delivered shortly after Obama was declared the victor, McCain told a crowd of disappointed supporters, "We have come to the end of a long journey. The American people have spoken and they have spoken clearly."
McCain said he'd called Obama to offer his congratulations, and acknowledged the historic nature of his rival's win. "This is an historic election and I recognize the special significance it has for African Americans," said McCain. "I have always believed that America offers opportunities for those who have the will to seize it … Let there be no reason for any American to fail to cherish their citizenship in this, the greatest nation on earth."
President Bush also called Obama to congratulate him on his victory.
Obama's onetime rival for the Democratic nomination, Hillary Clinton, said in statement, "Tonight, we are celebrating an historic victory for the American people. This was a long and hard fought campaign but the result was well worth the wait."
In a presidential campaign that stretched over two years, Obama triumphed with the help of early support from Oprah Winfrey and endorsements from a variety of Hollywood stars like Scarlett Johansson and Matt Damon. Only last weekend, he was serenaded in concert by Bruce Springsteen.
'Transformational Figure'Since first appearing on the national stage only four years ago, when he walloped Illinois radio host Alan Keyes to become a U.S. senator, the Chicago Democrat, 47, has emerged as his generation's political rock star, forging a path to the White House with sharp focus and stunning speed.
Always, it seemed, there were huge crowds gathered to see the charismatic candidate, whom Colin Powell, in his own endorsement of Obama, labeled "a transformational figure."
But there were tough personal times, too, such as when Obama broke off campaigning for two days in the final stretch to visit his gravely ill grandmother, Madelyn Dunham, 86, in Hawaii. Dunham died two days before the election, never living to see Obama rise to this pinnacle.
The president-elect takes with him to the White House on Inauguration Day Jan. 20 his wife of 16 years, Michelle Obama, and their two daughters, Malia, 10, and Sasha, 7.
Obama is expected to make his victory speech at a rally in Chicago's Grant Park, where 70,000 guests received coveted tickets to the event – and up to 1 million people could show up, according to Chicago authorities.
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