It would be an understatement to say actor George Clooney overshadowed Kansas Sen. Sam Brownback at a Thursday news conference to raise awareness of the humanitarian crisis in the Darfur region of Sudan.

The Oscar winner, back from a five-day trip to the region with his father, Nick, told a packed room at the National Press Club that he wants to use his “credit card” as a Hollywood star to focus attention on the plight of 2 million desperate refugees in the war-torn area.

“Is the American government slow to act? Of course we’re slow to act. We always are,” Clooney said, referring to prior U.S. intervention in Rwanda and the Balkans.

“It’s something that has to start today,” Clooney said. “If we don’t get to work on it today, there’s a few thousand people who will be dead by the end of the week.”

Traveling the region with a cameraman, Clooney and his father – a former television anchorman – documented the horrible conditions in Sudanese refugee camps. He showed video excerpts of their interviews with families describing how militias kill civilians, rape women and lay waste to villages.

“What we cannot do is turn our heads and look away and hope that this will somehow disappear,” said Clooney, who won a best supporting actor Oscar for his role in the politically charged thriller “Syriana.”

Academy Award winning actor George Clooney, center, flanked by Sen. Barack Obama, D-Ill., right, and Sen. Sam Brownback, R-Kan., takes part in a news conference at the National Press Club in Washington, Thursday, April 27, 2006 to bring awareness to the situation in the Darfur region of Sudan.

“If we do, it will disappear and an entire generation will be gone and then only history will be left to judge us,” Clooney said.

Clooney and his father plan to attend a massive Darfur rally Sunday on the National Mall in Washington. Rallies are planned this weekend in more than a dozen other cities.

Clooney, who turns 45 next week, was joined Thursday by Brownback, a Republican, and Sen. Barack Obama, an Illinois Democrat. They are co-sponsors of a measure working its way through Congress that would boost funds for peacekeeping and humanitarian aid to Darfur.

The lawmakers – who could not be further apart on most political issues – thanked Clooney for his efforts and called on the Bush administration to appoint a special envoy to the region. They also want a U.N. protection force mobilized to protect refugees from further atrocities.

Brownback did not seem to mind that Clooney was the big draw Thursday. His news conferences on Sudan usually garner little interest from the news media.

Given the serious tone of the news conference, none of the reporters dared to shout out any questions about Clooney’s latest Hollywood projects or his reaction to being named again to People magazine’s annual “100 Most Beautiful People” list.

“By you going, you draw attention and we get this,” Brownback told Clooney, pointing to the throngs of reporters crammed in the press club meeting room. Brownback, a possible 2008 presidential candidate, has been a leader in raising awareness on Darfur.

“This is the first genocide of the 21st century,” Brownback said.

The United States already has authorized more than $300 million to help victims of violence and support peace talks in Sudan. President Bush has said he favors an expanded international role in Darfur, backing a larger security force and NATO involvement.

The conflict began in 2003, when rebels of ethnic African tribes took up arms against the Arab-dominated government, complaining of discrimination and mistreatment. The government responded with a brutal counterinsurgency led by Arab militias, known as the Janjaweed. At least 180,000 have died, mainly of hunger and disease.