Thousands of cheering voters welcomed Barack Obama to a packed arena in St. Paul, Minnesota, late Tuesday night, where the Illinois Senator declared victory in the Democratic Party's primary race.
Earlier in the night, Obama had reached the number of delegates needed to win the nomination, making him the first African-American to lead a major U.S. party in a presidential campaign.
"Our primary season has finally come to an end," he declared.
"I will be the Democratic nominee for the presidency of the United States of America."
Obama thanked all of his rivals in the race, with whom he said he competed as a rival and learned from as friends.
He singled out Hillary Clinton -- and gave a nod to former President Bill Clinton. He said both had fought tirelessly for average Americans.
"(Hillary Clinton) is a leader who inspires millions of Americans with her strength and courage ... I congratulate her on the race she has won throughout this contest."
He said the country is better off because of her and "I am a better candidate because of her."
Obama then turned to the crowd -- which yelled euphorically, "Yes, we can."
"Let us work together to chart a new course for America," Obama shouted. "America, this is our moment. This is our time."
Obama's course will run directly into the path of a general presidential fight with Republican nominee John McCain. Obama said that McCain was once a maverick, but has "embraced George Bush's policies."
McCain, Obama declared, does not offer what the U.S. needs in foreign affairs and domestic policies. He said the country needs change and a new direction.
By the time of Obama's speech he was on his way to victory in Montana's primary race -- but was projected to lose to Hillary Clinton in South Dakota. The two states are the last two states in the Democratic race.
Clinton's speech
Just minutes before Obama's speech, Clinton -- who finished a close second in the primary race -- congratulated Obama on running a good campaign during the primary season.
She said it was "an honour" to contest the primaries with Obama, "my friend." But Clinton fell short of conceding defeat and did not acknowledge that Obama had the delegates necessary to claim the mantle of the Democratic Party leadership.
"I will be making no decisions tonight (about my future)," she said, as a crowd cheered her on, yelling "Denver. Denver. Denver."
Denver will be the site of the Democratic Party convention later this summer where the party's nominee will be officially declared.
Said she wanted to hear from her voters and "in the coming days will consult with party leaders" to determine how she will move forward.
John McCain takes aim
Obama's Republican opponent took the opportunity Tuesday to launch the first salvo in the run-up to November's general election.
Sen. McCain told supporters in New Orleans that 2008 will present a major opportunity for change, "but the choice is between the right change and the wrong change."
McCain said he believes Obama will take the country in the wrong direction. He added he was surprised that the "young man has bought into so many failed ideas."
He portrayed Obama as a tax-and-spend liberal, repeating the phrase, "That's not change we can believe in."
McCain tried to distance himself from U.S. President George Bush, whose popularity has plummeted in the past year.
McCain also praised Clinton, saying that he and American women owe her a debt for providing inspiration.
Earlier on Tuesday, The Associated Press said that Obama had reached the number of delegates needed to become the Democratic nominee. He will be the first black man to lead a major U.S. party in a presidential campaign.
The AP tally includes those who have only privately confirmed their intentions. It also takes into account delegates likely to be awarded in tonight's primaries in South Dakota and Montana.
On Tuesday afternoon, Clinton said she would be "open" to the idea of being Obama's running mate. Clinton reportedly made the remarks during an afternoon conference call among members of the Democratic Party's New York congressional delegation.
During the phone call, Rep. Lydia Velasquez said she thought Clinton could help Obama win over Hispanics and other key voting blocs. Clinton replied, "I am open to it," adding she would do what was required to help the party win the November election.
Obama needed at least 2,118 delegates to secure the nomination.
Clinton's chances to win the nomination diminished greatly this past weekend when the Democratic Party's rules and bylaws committee seated Florida and Michigan. They were primaries she had won but previously had not been counted because the states had broken party rules by holding early contests.
Clinton had argued that both states should be seated fully -- and that Obama should not get any delegates from Michigan, where his name was not on the ballot. Instead, the committee ruled that both candidates would receive delegates from the states, netting Clinton 24 delegates, a total far less than she had hope for.
With his razor-thin victory, Obama is coming off a tough primary season that saw record voter turnouts. The two candidates slugged it out week after week beginning in January. The race likely turned in Obama's favor in February after he won more than a dozen straight caucus and primary victories.
However, Clinton always appeared to come back and win in key states, such as Pennsylvania and Ohio, likely battlegrounds in the general election.
With files from The Associated Press
