*Barack Obama, the Democratic senator from Illinois captured the White House on Tuesday after an extraordinary two-year campaign, defeating Republican John McCain to make history as the first black U.S. president.
Obama will be sworn in as the 44th U.S. president on January 20, 2009 and will face a crush of immediate challenges, from tackling an economic crisis to ending the war in Iraq and trying to overhaul the U.S. health care system.
McCain saw his hopes for victory evaporate with losses in a string of key battleground states led by the big prizes of Ohio and Florida, the states that sent Democrats to defeat in the last two elections.
The win by Obama, son of a black father from Kenya and white mother from Kansas, marked a milestone in U.S. history. It came 45 years after the height of the civil rights movement led by Martin Luther King.
"It's been a long time coming, but tonight, because of what we did on this day, at this defining moment, change has come to America," Obama, 47, told 125,000 ecstatic supporters gathered in Chicago's Grant Park to celebrate.
"The road ahead will be long. Our climb will be steep. We may not get there in one year or even one term, but America -- I have never been more hopeful than I am tonight that we will get there," he said.
Obama led sweeping Democratic victories that expanded the party's majorities in both chambers of Congress and marked an emphatic rejection of President George W. Bush's eight years of leadership.
McCain, a 72-year-old Arizona senator and former Vietnam War prisoner, called Obama to congratulate him and praised his rival's inspirational and precedent-shattering campaign.
"We have come to the end of a long journey," McCain told supporters. "I urge all Americans who supported me to join me in not just congratulating him but offering our next president our goodwill."
News of Obama's win set off celebrations by supporters around the country, from Times Square in New York to Ebenezer Baptist Church in Atlanta, King's home church.
"This is a great night. This is an unbelievable night," said U.S. Rep. John Lewis of Georgia, who was brutally beaten by police in Selma, Alabama, during a voting rights march in the 1960s.
The Rev. Jesse Jackson, a civil rights leader, joined the celebrations in Chicago, tears streaming down his cheeks.
In addition to Ohio and Florida, Obama won Virginia, Iowa, New Mexico, Nevada and Colorado -- all states won by Bush in 2004. McCain's loss in Pennsylvania eliminated his best hope of capturing a Democratic-leaning state.
Obama was on the way to winning more than 300 Electoral College votes, far more than the 270 needed. With nearly two-thirds of U.S. precincts reporting, he led McCain by 51 percent to 48 percent in the popular vote.