Sen. Barack Obama achieved the 2,118 needed to clinch the Democratic nomination for president last night and made history by becoming the first African American to win a major party's presidential nomination.
Obama, D-Ill., locked up one of the longest and most closely fought Democratic nomination fights in recent history.
"Tonight we mark the end of one historic journey with the beginning of another -- a journey that will bring a new and better day to America. Because of you, tonight I can stand before you and say that I will be the Democratic nominee for president of the United States," Obama told 30,000 thrilled supporters at an arena in St. Paul, Minn.
"This is our time. This is our moment," he said.
He graciously praised Cllinton, despite the sometimes bitter exchanges the two had during the campaign.
"Senator Hillary Clinton has made history in this campaign, not just because she's a woman who has done what no woman has done before, but because she's a leader who inspires millions of Americans with her strength, her courage, and her commitment to the causes that brought us here tonight," Obama said.
"Our party and our country are better off because of her, and I am a better candidate for having had the honor to compete" with her, he said.
The presumptive Democratic nominee locked up the nomination even before the votes were counted in the party's final two primaries in South Dakota and Montana last night.
Obama went on to easily win Montana last night by a margin of 57 percent to Sent. Hillary Clinton's 42 percent. But Clinton, D-NY, snatched one last upset victory in South Dakota, with a 55-44 percent win.
Nevertheless, Obama picked up enough delegates from those states to pad his margin of victory and saw additional superdelegates rally to his side.
Later, the candidates played some phone tag, ABC's Sunlen Miller reports. A little after 11 pm, Obama left Clinton a message on an aide's cell phone, congratulating Clinton on her South Dakota win and asking that she return the call.
ABC's Eloise Harper reports that some time later, Clinton returned Obama's call. The two spoke very briefly and then the cell phone call dropped out. Clinton called him back and got his voice mail.
The two exchanged a couple more messages and finally spoke just after midnight. Obama reiterated his invitation from a conversation earlier in the week when he suggested that the two schedule a meeting. Clinton agreed, but no specific plans were made for a time or place for such a meeting.
For her part, Clinton refused to concede the race tonight.
"This has been a long campaign, and I will be making no decisions tonight," she told supporters in New York.
"In the coming days, I'll be consulting with supporters and party leaders to determine how to move forward with the best interests of our party and our country guiding my way," she said as supporters chanted "Denver, Denver!" pointing to the party's convention in August.
Clinton's campaign has indicated her willingness to challenge a Democratic Party ruling on Michigan and Florida's disputed delegates all the way to the Denver convention -- a drastic option that would delay the party uniting behind Obama.
However early Wednesday Democratic leaders signaled their unwillingness to go without a nominee before the convention.