Democrat John Edwards endorsed former rival Barack Obama on Wednesday, a move designed to help solidify support for the party's likely presidential nominee even as Hillary Rodham Clinton refuses to give up her long-shot candidacy. Edwards made a surprise appearance with Obama in Grand Rapids, Michigan, as the Illinois senator campaigns in a critical general election battleground state. The endorsement came a day after Clinton defeated Obama by more than 2-to-1 in the West Virginia primary. The loss highlighted Obama's challenge in winning over the "Hillary Democrats" - white, working-class voters who also supported Edwards in significant numbers before he exited the race in late January. Edwards, who received a thunderous ovation when Obama introduced him to a crowd of several thousand, said, "brothers and sisters, we must come together as Democrats" to defeat McCain. "We are here tonight because the Democratic voters have made their choice, and so have I." Obama has 1,887 delegates, leaving him 139 delegates short of the 2,026 needed to clinch the nomination. Clinton has 1,718 delegates, according to the latest tally by The Associated Press.