Obama builds unassailable lead over Clinton

Refusing to bow out of the race despite losing her only chance to catch up with Obama, Clinton, 60, declared, "It's full speed onto the White House".

Pointing that he was "less than 200 delegates away from the nomination", Obama, 47, told cheering supporters "there are those who were saying that North Carolina would be a game-changer in this election. But today what North Carolina decided is that the only game that needs changing is the one in Washington DC".

In North Carolina, Obama won 56 per cent of the vote to 42 per cent for Clinton while in Indiana, Clinton got 51 per cent of the vote compared with her rival's 49 per cent.

Obama won at least 94 delegates and Clinton at least 75 in the last of the big-ticket states combined, with 18 still to be awarded, according to an Associated Press count.

The first-time Senator from Illinois led with 1,840.5 delegates, including separately chosen party officials known as superdelegates. Clinton had 1,684 delegates.

Obama, who is bidding to be the first black president of the United States, was 184.5 delegates shy of the 2,025 needed to secure the Democratic nomination at the party's convention this summer in Denver.

With her loss in North Carolina, Clinton has little hope of narrowing the gap and almost no chance of winning enough elected delegates to overtake Obama. The primaries now left are West Virginia (28 delegates) on May 13, Oregon (52) and Kentucky (51) on May 20, Puerto Rico (55) on June 1, and Montana (16) and South Dakota (15) on June 3.

Targeting the presumptive Republican nominee Senator John McCain and the Grand Old Party, Obama said, "While I honour John McCain's service to his country, his ideas for America are out of touch with these core values. His plans for the future, of continuing a war that has not made us safer, of continuing George Bush's economic policies that he claims have made great progress, these are nothing more than the failed policies of the past."

Meanwhile, officials in Lake County in Indiana were saying that they would not make any announcement until after all absentee ballots, numbering 11,000 plus, were counted.