The Rally to Stop Genocide -- with a crowd estimated by organizers at 10,000 to 15,000 -- drew a wide range of supporters from politicians and celebrities to students and religious groups. The prevailing message was to urge President Bush to take stronger measures to end the violence in Darfur.

In 2004, the House of Representatives approved a measure declaring the slaughter of mostly black African Muslims by Arab militias in Darfur "genocide." Since then, the House and Senate have urged stronger peacekeeping missions and approved billions of dollars in aid to Sudan and the Darfur region of the East African nation.

But the demonstrators and speakers said more action is needed with an estimated 200,000 people killed and 2 million displaced from their burned villages to refugee camps.

Rep. Michael Capuano, D-Mass., told the Online NewsHour the United States needs "to step it up a little bit with supplemental spending, but we need to show more leadership in the international community."

The United States supports additional North Atlantic Treaty Organization troops in Darfur, as well as a stronger U.N. peacekeeping force with a robust mandate to protect civilians.

The government of Sudan denies it is currently arming the Arab militia, called the Janjaweed, and says it is committed to peace talks with rebel groups. The rally coincided with the original deadline for the government and rebel groups to sign an African Union-sponsored peace plan.

The government has agreed to the terms of the deal, but rebel groups are having trouble deciding among themselves whether to accept the plan. The AU has extended the deadline for the groups to decide until Tuesday.

The day of the rally began with an appeal from southern Sudanese refugees from the group Sudanese Standing Together chanting, "No more Janjaweed. No more killing. No more raping. No more genocide."

The refugees and others expressed their gratitude to the Bush administration for its support in Darfur, but said U.N. sanctions should be enacted to prevent further killings.

Peter Adam, who works with refugees from Darfur in eastern Chad, said, "We need to stop genocide right now. We hope that the United States government will help to compel the government of Sudan to realize that they need to sign the peace agreement in Abuja."

Another large contingent at the rally was Jewish Americans, who said they were appalled by the conflict in the Sudan. Busloads of Holocaust survivors, World War II veterans and Jewish youth attended the rally. They held signs that drew parallels to the Holocaust and how the world remained silent as Jews were killed.

Debbie Radov from the Westchester Reform Temple in Scarsdale, N.Y. said she was motivated by her Rabbi Richard Jacobs who traveled to Darfur in 2005 and was the convocation speaker at the rally. Like many others, she urged the United Nations to send peacekeepers into Darfur and hoped that the gathering would encourage America to appropriate more money to stop the genocide.

"We want the world to listen and not to turn a deft ear. We want the world to take economic sanctions against the Sudan so that they can turn their head and their minds and their hearts away from this action that they are pursuing at the moment," said Radov.

College students from across the country also came in droves. They urged universities to disinvest from companies doing business with Sudan, and helped organize postcard campaigns to generate support for Darfur.

Brian Schwartz, an organizer from the University of Illinois' student group Action Darfur which has grown into a network of 12 universities, drove 18 hours to the rally with 110 other college students to show their support.

He said he hopes "to see a NATO presence to bridge the gap for the United Nations to blue hat the African Union force."

His coalition partner Dominique Franco from Parkland College added, "It would be great if we could work with the French troops in Chad and get a no-fly zone. Helicopters are one of the ways they are killing so many people."

The Save Darfur coalition, which hosted the rally, is an alliance of over 160 faith-based groups including religious and secular Jews, evangelical Christians, Catholics, Muslims, Buddhists, black churches, human rights organizations and Arab groups.

The list of speakers included Sen. Barack Obama, D-Ill.; Elie Wiesel, Holocaust survivor and recipient of the Nobel Peace Prize; the Rev. Al Sharpton; actor George Clooney and his father Nick Clooney, who recently traveled to Darfur and have taken up the refugees' cause; Olympic speedskater Joey Cheek, who donated his medal winnings to the Darfur cause; and Russell Simmons, the Founder of Def Jam Records.

-- By Kathryn Cohen, Online NewsHour