Barack Obama broke through the racial barrier to the Oval Office, becoming the first African-American to gain the presidency. And his electoral landslide delivered a powerful message about a new generation of American leadership.
The young and minority voters who helped lift the 47-year-old Democrat to the White House are now the foundation of a new majority in U.S. politics. Their emergence likely brings to a close the era of conservative dominance that began with Ronald Reagan's election almost three decades ago.
Obama's campaign, perhaps the most brilliantly run in the modern era, reflected the multicultural diversity of 21st-century America. He sought to move beyond old racial divides, but his victory also means that a descendant of slaves will become first lady of the United States for the very first time.
"A new dawn of American leadership is at hand," the president-elect said last night. "To those who would tear this world down - we will defeat you. To those who seek peace and security - we support you. And to all those who have wondered if America's beacon still burns as bright - tonight we proved once more that the true strength of our nation comes not from the might of our arms or the scale of our wealth, but from the enduring power of our ideals: democracy, liberty, opportunity and unyielding hope."
As a breakthrough, his rise to power surpasses that of John F. Kennedy, because the obstacle Obama surmounted was greater than the sectarian prejudice against Catholics. His ascent is a landmark in America's long, primal struggle over race.
"It's a major milestone," said Rep. Elijah E. Cummings, a Baltimore Democrat and leading Obama supporter. "So often the African-American people have felt as if they were invisible. ... The impact of this will be felt for a very, very, very long time."
John McCain, in his concession speech, saluted Obama's historic achievement and paid special tribute to his success in "inspiring the hopes of so many millions of American who once wrongly believed that they had ... little influence in the election of an American president."
In many quarters overseas, where the presidential contest was followed almost as avidly as in the U.S., international polling showed that Obama was a heavy pre-election favorite. His victory, analysts said, is likely to be greeted as a corrective to the damage that America's image has suffered in recent years.
Through a democratic vote, the citizens of the globe's superpower demonstrated that America remains an open society. They handed authority to the son of a Kenyan father and a Kansan mother whose middle name, Hussein, is as common in Arab countries as it is rare in the United States.
Widespread dissatisfaction with a badly slumping economy hurt John McCain's chances, as Obama blew past the share of the popular vote won by the last Democrat to get a popular majority, Jimmy Carter, with 50.1 percent in 1976.
Based on incomplete returns, Obama seemed to be piling up the biggest vote by a Democrat since Lyndon B. Johnson in 1964. Some of the places that fell his way, including Virginia, had not gone Democratic since that time.
Obama wrestled key battlegrounds, such as Ohio, away from the Republicans by winning independents, improving Democratic margins among Catholics and white suburbanites and, perhaps most of all, capitalizing on sharp disapproval with President Bush's leadership. More than a third of all voters said they wanted a candidate who would change Washington, and Obama won their votes by a wide margin, according to exit polls.
The one-time community organizer, whose campaign invested heavily in new voter registration, particularly among minorities and those under 30, saw that strategy pay off handsomely. About one in seven of Obama's votes came from those taking part in their first election.
Overall, about one in five new voters were black, double their proportion in the overall electorate, and another one in five were Hispanic.
Obama won two-thirds of voters under 30; four years ago, a bare majority in that age group backed Democratic nominee John Kerry over Bush. McCain ran best among those over 65.
Record turnout by African-Americans, many of whom never believed they would see this day, was also key. Obama won all virtually their votes. In 2004, Bush got about 11 percent of the black vote.
Obama also won about two-thirds of Hispanics, which boosted him to victory in emerging Southwest battlegrounds of Nevada, New Mexico and Colorado. Four years ago, Bush took more than 40 percent of the Hispanic vote, part of a concerted drive for the nation's largest and fastest growing minority. McCain drew only about 30 percent, in spite of his political roots in Arizona.
Obama's considerable gifts as a politician helped bring him from obscurity to the leadership of the country in a few short years.
His cool demeanor and rich baritone voice helped generate an emotional appeal that began to become clear outside his home state of Illinois when he campaigned for fellow Democrats in the 2006 election.
He was quickly marked as a once-in-a-generation politician, and his charisma prompted comparisons to the Kennedys. In a symbolic torch-passing during this year's primaries, the surviving Kennedy brother, Massachusetts Sen. Edward M. Kennedy, endorsed Obama, as did the late president's daughter, Caroline, a late-blooming campaigner now talked about as a possible member of the new administration.
Obama owed his triumph, in considerable measure, to millions of volunteers, many of them young, who mobilized on his behalf and formed the nucleus of a new political machine now positioned to expand its influence in coming months.
The breadth of the liberal Democrat's victory - based on his brief record in elective politics, he could well be the most liberal president since Johnson - will likely strengthen his hand once he takes office.
Less clear, however, given the country's highly uncertain economic future, is the precise direction he intends to take. Obama ran a non-ideological campaign and is expected to give prominent Cabinet seats to Republicans, in an effort to cast himself as a centrist president who would reach across party lines.
The overriding message of change that he delivered over the past 21 months, since announcing his candidacy with strong Lincolnian overtones at the old statehouse in Springfield, Ill., has included a call for ending Washington's petty politics and the excessive influence of special interests.
But a bulked-up Democratic majority in Congress, one of the byproducts of the Obama landslide, will likely embolden members of the new president's party to make up for legislative setbacks under Bush. That could put unwanted pressure on Obama at the start of his term and complicate his efforts to govern from the center at a time of national economic crisis.
He will undoubtedly claim a mandate in his sweeping win, which owed much to a revolutionary campaign apparatus that reinvented politics by marrying the Internet and modern communications technology in spectacular fashion.
His remarkable success in raising far more money than most strategists thought possible enabled him to dethrone his party's reigning family, the Clintons, and gave him powerful leverage in the general election.
In the first presidential election since 1960 to take place in what many believe is a recession, more than six in 10 voters called the economy the most important issue facing the country; nine in 10 voters were pessimistic about the economy's direction.
McCain's image as a one-time Bush critic was undercut by Obama's relentless, and ultimately successful, efforts to tie him to the president, whose policies he largely backed.
McCain also was hurt by his running-mate selection of Sarah Palin, a governor of Alaska with even less experience at the state and national levels than Obama. Exit polls showed that one-fourth of independents, a key swing group, said Palin was an important factor in deciding who they would support and most backed Obama.
Nearly half of moderates also called Palin a factor - and most of them voted for Obama.