Democrats choose Obama in thunderous acclamation

DENVER -- Barack Obama stepped into history Wednesday night, the first black American to win a major party presidential nomination, as thousands of Democrats transformed their convention hall into a joyful, shouting celebration.

Former rival Hillary Rodham Clinton asked delegates to the party convention to make their verdict unanimous "in the spirit of unity, with the goal of victory." And they did, with a roar.

Competing chants of "Obama" and "Yes we can" surged up from the convention floor as the outcome of a carefully scripted roll call of the states was announced.

Not long afterward, former president Bill Clinton delivered his own strong pitch for the 47-year-old first-term senator from Illinois.

"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.

Michelle Obama, watching from her seat in the balcony, stood and applauded as the former president praised her man.

Obama was across town as the party handed him its top prize -- a ticket into the general election campaign against Republican Sen. John McCain. He was expected to briefly visit the Pepsi Center later in the evening to thank the delegates.

His formal acceptance speech tonight is expected to draw a crowd of 75,000 at the nearby football stadium where an elaborate backdrop was under construction.

The evening program also included the delegates' acceptance of Obama's choice of Delaware Sen. Joseph Biden as vice presidential running mate. Biden had the marquee time spot for his acceptance speech late Wednesday.

Obama made an unscheduled and unscripted appearance at the convention, joining Biden on the platform.

Hillary Clinton's call for Obama to be approved by acclamation -- midway through the traditional roll call of the states -- was the culmination of an agreement worked out between the two camps to present a unified front after their long and often-bitter fight for the nomination.