Democratic Senator Hillary Rodham Clinton on Saturday officially launched her campaign to become the first woman president of the United States.

"I'm in. And I'm in to win," Hillary, a former first lady now representing New York in the US Senate, said in a banner headline on her Web site.

The announcement was being anticipated for several weeks with polls showing that she leads for the Democratic presidential nomination, topping John Edwards and Senator Obama Barack who is bidding to become first black president of the country.

In a videotaped message on the Web site, Hillary said: "After six years of George W Bush, it is time to renew the promise of America. Today I am announcing that I will form an exploratory committee to run for president. And I want you to join me not just for the campaign, but for a conversation about the future of our country."

She said the "stakes will be high" when America chooses a new president in 2008.

"As a Senator, I will spend two years doing everything in my power to limit the damage George W Bush can do. But only a new president will be able to undo Bush's mistakes and restore our hope and optimism.

"Only a new president can renew the promise of America -- the idea that if you work hard you can count on healthcare, education and retirement security that you need to raise your family. These are the basic values of America that are under attack from this administration every day.

"And only a new president can regain America's position as a respected leader in the world," Hillary said.

"This is a big election with some very big questions. How do we bring the war in Iraq to the right end? How can we make sure every American has access to adequate health care? How will we ensure our children inherit a clean environment and energy independence? How can we reduce the deficits that threaten Social Security and Medicare?," Hillary added.

The Democratic Party has attracted a slew of candidates who have expressed keen interest in pursuing the White House in 2008.

New Mexico Governor Bill Richardson, who is Hispanic, plans to announce his bid for the White House on Sunday, which would make the Democratic field very diverse with a woman, a black and a Hispanic vying to score first in the next year's elections.

Analysts say that though the former first lady enjoys strong loyalty from her core supporters, she also attracts strong opposition from her detractors and then there is the issue of whether Americans are ready to have a woman as their president.

However, they also concede that the Clintons are very adept at organising successful election campaigns and fundraisers. She has strong support from her husband, former president Bill Clinton, who still has the charisma to attract crowds.

The list of potentials of the party also includes Senate Foreign Relations Committee Chairman Joseph Biden and Senator Christopher Dodd of Connecticut. There is even persistent talk that former vice president Al Gore could throw his hat in the ring.