Hundreds of thousands of abortion-rights supporters marched on Washington Sunday, protesting Bush Administration policies they feel encroach on a woman's choice to terminate her pregnancy.

Politicians and celebrities joined the crowd which gathered at the base of the Capitol and stretched to the Washington Monument.

"This administration is filled with people ... who consider Roe v. Wade the worst abomination of constitutional law in our history," said Democratic Sen. Hillary Clinton of New York, referring to the 1973 Supreme Court decision legalizing abortion.

Women march down Pennnsylvania Avenue in Washington Sunday during a abortion-rights rally and march. (AP Photo)

Bush, who opposes abortion rights, has angered critics by signing a ban on partial-birth abortions. The law gives legal rights to a fetus separate from the pregnant woman.

Abortion-rights supporters also worry the Roe v. Wade decision could be overturned if Bush fills Supreme Court vacancies with anti-abortion judges.

Whoopi Goldberg, Kathleen Turner, Cybill Shepherd, Lynda Carter and media mogul Ted Turner were among the celebrities leading the march.

Camryn Manheim, left, Cybill Shepherd, Whoopi Goldberg, center, Ashley Judd, and Christine Lahti, back right, march in Washington Sunday during an abortion-rights rally (AP Photo)

"There is a religious and moral superiority and arrogance that so many, not all, Republicans have," said actress Linda Carter. "It is the ultimate intrusion by government to tell a woman when she can have children, if she has them at all."

But Kate Michelman, president of NARAL Pro-Choice America, said the march was about more than abortion rights.

"The march is about the totality of women's lives and the right to make decision about our lives," she said.

Organizers set up voter registration tables to support John Kerry, the Democratic presidential candidate. Kerry is pro-choice.

Smaller pro-choice rallies were also held in Vancouver, Halifax and Ottawa.