Barack Obama makes history as Democrats' presidential nominee

His nomination Wednesday at the Democratic National Convention also put Obama, the son of a black Kenyan father and a white American mother, just one victory away from taking charge of a nation where, just decades ago, many black people were unable to vote.

He walked unannounced onto the stage after running mate Joe Biden used a rowdy vice presidential acceptance speech to laud Obama and to tear into Republican rival John McCain, even as he called him a "friend" whose "personal courage and heroism ... still amaze me."

Obama, delighting the crowd with his appearance, praising the one-time frontrunner for the Democratic nomination Hillary Clinton, and her husband former President Bill Clinton, as well as his wife for their prime time speeches in support of him this week.

"If I'm not mistaken, Hillary Clinton rocked the house last night!" he shouted. Obama's wife, Michelle, who delivered a tone-perfect address to open the convention could be seen mouthing the words "I love you" from her VIP seat in the Pepsi Center.

The long Democratic soap opera near an end - and the Obama campaign no doubt heaved a sigh of relief - after rousing speeches on Obamas behalf by the Clintons - Hillary on Tuesday and Bill Clinton, the former president, on Wednesday. They offered unabashed praise for their one-time opponent, whom they had sharply criticized through the grueling 18-month primary contest.

That cleared the way for Obama to formally accept the party's nomination before 75,000 people in a Denver sports stadium Thursday night.

Given the country's tortured racial history, the decision is a gamble for the Democrats as they symbolically opened the fall campaign to take back the White House from the Republicans, who will nominate McCain, the 72-year-old senator and former Vietnam war hero, next week.

While healing the Democratic party may still prove difficult, the process began effusively Tuesday night when Hillary Clinton said Obama is "my candidate, and he must be our president."

Bill Clinton echoed his wife’s words the night following, noting that she had told the convention she would do everything possible to get Obama elected. "That makes two of us," he said.

For months, the former president had made little secret of his disappointment over his wife's primary defeat. During her campaign, he faced criticism for his outbursts of anger and deprecatory comments about Obama.

But his 1993-2001 presidency is warmly remembered by Democrats as a time of peace and prosperity, and Clinton was greeted with a huge and extended ovation as he took the stage. He was interrupted frequently by applause as he praised Obama.

"Everything I've learned in my eight years as president and the work I've done since, in America and across the globe, has convinced me that Barack Obama is the man for this job," he said.

While there were no surprises in the convention, drama was heightened as both Obama and Clinton's names were put in for the nomination. Convention leaders were well along in a state-by-state roll call vote when the New York senator strode into the midst of her delegation as planned and stopped the process, calling for Obama's unanimous nomination "in the spirit of unity, with the goal of victory."

The delegates agreed with a roar and Nancy Pelosi, the speaker of the House of Representatives and titular head of the convention, pounded her gavel on the historic vote.

Despite having released her delegates earlier in the day, Clinton received 341 votes to Obama's 1,549 before she called for him to be approved by acclamation.

Clinton, who won nearly 18 million votes in the state primaries but could not overcome Obama's delegate total, had wanted the pro forma roll call as a cathartic moment for her huge bloc of supporters.

Tensions between the two camps were aggravated last week by Obama's decision to name Biden instead of Clinton as his vice presidential running mate. But in their speeches, both Clinton's commended the choice.

Biden received the vice presidential nomination by acclamation Wednesday night, and in accepting he declared he had learned the quality of Obama’s mind and character while campaigning against him in the primary.

"I watched how Barack touched people, how he inspired them, and I realized he had tapped into the oldest American belief of all: We don’t have to accept a situation we cannot bear. We have the power to change it," he said.

Obama has campaigned on a theme of hope and change, tapping into voter dissatisfaction with the old politics of Washington and the unpopular presidency of Republican George W. Bush.

He was little known outside his home state of Illinois until 2004 when, as a candidate for the Senate, he dazzled with a keynote address at the Democratic National Convention. He won election to the Senate, then announced his presidential candidacy a scant two years after arriving in Washington.

With his gifts as a speaker, his astounding ability to raise money on the Internet and an unmatched ground operation pieced together by political veterans, he won a stunning victory in the first nominating contest, the Iowa caucuses on Jan. 3.

Obama has pledged to pull U.S. combat forces out of Iraq in 16 months and to make health care available to all Americans.

He has called for bipartisan unity and targeted western and southern states that have been Republican strongholds. But he is vulnerable in northern industrial states, Clinton strongholds that have been crucial to Democratic hopes.

Obama, his wife, Michelle, and Biden and his wife, Jill, will embark on a bus tour of three of those states: Pennsylvania, Ohio and Michigan.

Republicans hold their convention next week to anoint McCain as their candidate. He has not yet announced a running mate, but was expected to do so soon.

On Wednesday, McCain's campaign released a new TV ad saying that Obama showed he was "dangerously unprepared" for the White House when he described Iran as a "tiny" nation that did not pose a serious threat.

Missing from the ad was the context of Obama's remarks last May in which he compared Iran and other U.S. adversaries to the superpower Soviet Union.

In his speech, Bill Clinton defended Obama's national security credentials. Recalling that when he ran for president at age 46 in 1992, "Republicans said I was too young and too inexperienced to be president."

"Sound familiar?" Clinton said. "It didn't work in 1992, because we were on the right side of history. And it won't work in 2008, because Barack Obama is on the right side of history."