Obama takes eight straight wins

Barack Obama has extended his winning streak over US presidential hopeful Hillary Clinton after a fresh sweep of primary victories.

Mr Obama extended his winning streak to eight after he easily won Virginia, Maryland and the District of Columbia.

The man who hopes to be the first black president of the US said: "We have now won east and west, north and south, and across the heartland of this country we love."

According to one count, the Illinois senator had 1,078 pledged delegates to Mrs Clinton's 969. A candidate needs 2,025 to clinch the Democratic nomination.

"We believe it's next to impossible for Senator Clinton to close that pledged delegate count," said David Plouffe, Mr Obama's campaign manager.

"The only way she could do it is winning most of the rest of the contests by 25 to 30 points."

Meanwhile, Republican front-runner John McCain also swept to wins over his major challenger, former Arkansas Governor Mike Huckabee.

He said: "Now my friends comes the hard part, and for America, the much bigger decision.

"We do not know for certain who will have the honour of being the Democratic Party's nominee for president. But we know where either of their candidates will lead this country, and we dare not let them."

Mrs Clinton, a New York senator and wife of former President Bill Clinton, has voiced confidence about her campaign's future.

She has been hit by the resignation of deputy campaign manager Mike Henry. He was brought into the campaign by Patti Solis Doyle, who stepped down on Sunday.

Mrs Clinton is now focusing on next week's battles in Wisconsin and Hawaii and the crucial March 4 votes in the big states of Texas and Ohio.

She said: "We're going to sweep across Texas in the next three weeks. I'm tested, I'm ready, let's make it happen."

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