Obama turns focus to McCain, starts VP search

Clinton, in a later speech to the same group, complimented Obama and said she knew he would be a friend to Israel, but offered no signs of when she would end her campaign.

Clinton's supporters turned up the pressure for the New York senator to be named as Obama's vice presidential candidate. Robert Johnson, founder of Black Entertainment Television, said he wrote to the Congressional Black Caucus urging members to push Obama to choose Clinton.

Obama's campaign said the search was just beginning.

"Senator Obama is pleased to have three talented and dedicated individuals managing this rigorous process," spokesman Bill Burton said. "He will work closely with them in the coming weeks but ultimately this will be his decision and his alone."

The victory by Obama, son of a black Kenyan father and white mother from Kansas, marked a milestone in U.S. history. It came 45 years after the height of the civil rights movement and followed one of the closest and longest nomination fights in recent U.S. political history.

Obama clinched the win after a wave of uncommitted delegates announced their support on Tuesday, pushing his total well past the 2,118 needed to win. Clinton, who would have been the first woman presidential nominee in U.S. political history, won more than 1,900 delegates.

Obama's achievement drew praise from a Republican Secretary of State Condoleezza Rice, the highest-ranking black in President George W. Bush's Cabinet.

"It's a country that has overcome many, many, now years, decades of, actually a couple of centuries, of trying to make good on its principles," Rice said.

"And I think that what we're seeing is, an extraordinary expression of the fact that 'we the people,' is beginning to mean all of us," Rice said, a reference to the opening line of the U.S. Constitution.

(Additional reporting by Donna Smith, Caren Bohan, Thomas Ferraro, Ellen Wulfhorst and JoAnne Allen; Editing by Patricia Zengerle)

(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at blogs.reuters.com/trail08/)