Clinton vows to continue uphill bid

Hillary Clinton's landslide West Virginia victory barely made a dent in Barack Obama's big lead in the Democratic presidential race but she promised to keep pushing until the front-runner clinches the nomination.

Obama retains an almost unassailable advantage in delegates who will select the nominee at the party convention in August. He gained the support on Wednesday of two more superdelegates, who are free to back any candidate.

The new support came despite Obama's crushing 41-point loss in West Virginia, where he once again had difficulty attracting white working-class voters who have flocked to Clinton's side in the past few months.