Senator Hillary Clinton has urged millions of voters who supported her in the primaries to back presidential candidate Barack Obama. In a speech at the Democratic National Convention, Clinton called for party unity and said her one-time rival must be elected president. VOA Correspondent Meredith Buel has details from the convention site in Denver, Colorado.

Senator Hillary Rodham Clinton addresses Democratic National Convention in Denver, 26 Aug 2008

Clinton received an enthusiastic standing ovation at the convention, where not long ago it was widely expected that she would be anointed as the Democratic Party's choice for president.

But in a marathon and sometimes hostile primary campaign she lost to Barack Obama.

Clinton told her supporters they must now back Obama because the party does not have a moment to lose or a vote to spare.

"Whether you voted for me, or you voted for Barack, the time is now to unite as a single party with a single purpose," she said. "We are on the same team and none of us can afford to sit on the sidelines."

Clinton's ability to deliver her supporters, many of whom are still angry over the fierce battle for the nomination, could spell the difference between victory and defeat for Obama.

Polls show that a significant percentage of Clinton supporters say they intend to vote for Republican candidate John McCain in the November general election.

A straightforward endorsement of Obama by Clinton was considered critical to his campaign, and she delivered that Tuesday night, saying  "Barack Obama is my candidate and he must be our president."

Clinton criticized McCain, saying his election would lead to more war and less diplomacy.  

"We know that President Obama will end the war in Iraq responsibly, bring our troops home and begin to repair our alliances around the world," she said.

Former Virginia Governor Mark Warner gave the keynote address to the convention Tuesday night, saying McCain will follow the same economic and foreign policies as the Bush administration.

"This race is all about the future," he said. "That is why we must elect Barack Obama as our next president. Because the race for the future will be won when old partisanship gives way to new ideas. When we put solutions over stalemate and when hope replaces fear."

Wednesday's speeches at the convention will focus on national security and foreign policy.

They will showcase Obama's pick for vice president, Delaware Senator Joe Biden.

Obama is scheduled to address the convention on Thursday, when he accepts the Democratic Party's nomination.