Cantwell will meet with Washington state troops, the U.S. ambassador to Iraq, U.S. military officers and high-ranking Iraqi officials during the three-day visit.

She was to depart late Tuesday for Iraq aboard a military aircraft from Andrews Air Force Base, accompanied by Sens. Joseph Biden, D-Del.; Lindsey Graham, R-S.C.; and Saxby Chambliss, R-Ga.

The delegation will visit several polling places on Thursday, the final day of voting as Iraq elects a new parliament.

In statement before leaving, Cantwell said she was one of 79 senators calling for 2006 to be "a year of significant transition to full Iraqi sovereignty," with Iraqi forces taking the lead for the security of a free and sovereign Iraq.

"The elections in Iraq are an important act of democracy and an initial milestone for independence," she said, adding that President Bush and Congress must do a better job "making sure that troops are trained, infrastructure is secured and the international community is engaged to help the new government that emerges on Thursday stand on its own two feet."

Cantwell, who voted in favor of the war in 2002 and has supported all measures to fund it, has drawn criticism from state Republicans, who accuse her of flip-flopping on the war. Cantwell voted in favor of a Democratic amendment last month calling for a gradual withdrawal of U.S. troops from Iraq.

Washington state GOP Chairman Chris Vance called that vote hypocritical and suggested Cantwell is reacting to liberal critics who are dissatisfied with her support for the war.

"She is a politician with no real convictions, who will take whatever stance is popular at the time to get re-elected. She's a phony," Vance said last week.

Cantwell's statement did not address Vance's criticism, but she outlined what she called necessary steps for success in Iraq:

"First we must do a better job of training Iraqi troops and preparing them to take over their young nation's defense. We must focus on and protect critical assets like the electricity grid and pipeline security. Finally we must galvanize international support for this new Iraqi government."

Cantwell called Thursday's elections "a clear benchmark for Iraqi sovereignty" and said the U.S. must demand more accountability from the Bush administration.

"During this trip I will be looking at what progress is being made and what still needs to be done," she said.

Biden, the ranking Democrat on the Senate Foreign Relations Committee, said the main challenge after the election will be to ensure that Iraq's new parliament reaches political consensus on a constitution that protects the rights of all segments of the population and does not exacerbate the threat of civil war.

"The Iraqis want to vote. That doesn't mean they understand democracy," he said.