Democratic presidential contender Barack Obama won the endorsement of a key former rival Wednesday, one day after being trounced in the West Virginia primary by Hillary Clinton. VOA National correspondent Jim Malone reports from Washington.

Obama won the endorsement of former senator and Democratic presidential rival John Edwards.

Edwards made a surprise appearance with Obama at a campaign rally in Grand Rapids, Michigan.

"There's one man who knows in his heart that it is time to create one America, not two, and that man is Barack Obama," said Edwards.

Edwards dropped out of the race for the Democratic Party's presidential nomination earlier this year after disappointing finishes in the early primaries and caucuses.

Edwards could help shore up Obama's appeal among white working class voters, which has been a weakness for the Democratic frontrunner in several recent primaries.

The Edwards endorsement came one day after Obama was badly beaten by Hillary Clinton in the West Virginia primary, in large part because working class voters turned out to support her.

Despite her big win in West Virginia, most experts give Clinton virtually no chance of catching Obama in the overall delegate count.

In addition, Obama continues to outpace Clinton in securing the support of uncommitted so-called superdelegates, party activists and Democratic Party officeholders who can support either candidate.

Despite her long shot odds of winning the Democratic nomination, Senator Clinton defended her decision to remain in the race in an interview on NBC television.

"We're near the end of what's been a long process," she said. "I don't believe in quitting. I don't believe in being pushed out. I'm going to do everything I can be that nominee."

Clinton hopes her convincing victory in West Virginia will give her renewed momentum in the final five Democratic primaries, just as Obama is counting on a boost from the Edwards endorsement.

The states of Kentucky and Oregon hold primaries next Tuesday, and the primary season will come to a close on June 3. The Democrats hold their national nominating convention in Denver in late August to formally select a candidate to run against the presumptive Republican nominee, Senator John McCain.