Labor-friendly John Edwards in Obama's court

— -- Democrat John Edwards endorsed Barack Obama on Wednesday, as his former presidential rival tries to appeal to working-class voters who have been the bedrock of Hillary Rodham Clinton's support.

The endorsement by the former North Carolina senator, who sounded populist themes during his campaign, comes as Clinton refuses to give up her candidacy and Obama widens his lead in pledged delegates. Clinton trounced Obama by more than 2-to-1 in Tuesday's West Virginia primary, largely with the help of white, working-class voters.

"Democratic voters in America have made their choice and so have I," Edwards said, standing beside Obama at a raucous rally in Grand Rapids, Mich. "There is one man who knows in his heart that it is time to create one America and not two, and that man is Barack Obama.

Ferrel Guillory, a political scientist at the University of North Carolina at Chapel Hill, said Edwards' support "signifies a consolidation of Obama's status as the front-runner. It puts him closer to the nomination."

Obama and Clinton had been courting Edwards, the party's 2004 vice presidential nominee, since he dropped his bid in January. In March, Edwards said he had a "very high opinion" of his former rivals and that "we would be blessed as a nation" to have either of them in the White House.

But Obama was the candidate who came closest to Edwards' vision for change in government. In January, Edwards said he and Obama were both "powerful voices for change" even if they didn't agree on how that should occur.

Clinton campaign chairman Terry McAuliffe said he respects Edwards' decision. "But as the voters of West Virginia showed, this thing is far from over."

Obama also won the endorsement Wednesday of a leading abortion rights advocacy organization — a move swiftly denounced by a prominent women's group backing Clinton.

Nancy Keenan, president of NARAL Pro-Choice America, called Obama a "strong advocate of women's rights" and said his lead in fundraising and delegates demonstrates "he is going to be the nominee." Obama is within about 140 delegates of the 2,026 needed to clinch the nomination.