It's not easy to discern sharp differences between Washington's two major Senate candidates when it comes to Iraq, but voters are deeply split over the future of U.S. military involvement there.

About half of Washington voters believe the U.S. should withdraw from Iraq immediately or within 18 months, regardless of the political or security situation, a new poll commissioned by The Seattle Times found.

But nearly 40 percent of people surveyed said U.S. troops should leave only after Iraqi forces demonstrate an ability to keep peace, a position consistent with President Bush's. Six percent want the U.S. military to establish permanent bases there.

The poll, by Elway Research, shows wide divisions between Democratic and Republican voters on the future of American military policy in Iraq. Independents, who comprised the majority of poll respondents, showed an almost even split between setting a timetable for withdrawal and staying the course, but more than one in every five advocated immediate withdrawal.

Conducted Aug. 9-13, the poll of 403 registered voters statewide comes as Democratic Sen. Maria Cantwell and her likely Republican challenger, Mike McGavick, hone their positions on Iraq. Both say the issue will command attention until Election Day on Nov. 7.

Cantwell has been criticized by members of her party for not taking a strong stand against the war, but lately has spoken more forcefully against the administration's handling of Iraq.

McGavick, a former insurance executive, said that had he been in the Senate, he would not have voted to authorize force against Iraq in 2002 if he had known the country did not have weapons of mass destruction. Cantwell made a similar statement last week.

McGavick also said he would have accepted the resignation of Defense Secretary Donald Rumsfeld after the Abu Ghraib prison abuses came to light in 2004.

But he called Democrats' recent proposals to set a withdrawal timetable a "purely partisan exercise."

"If you look at most of Iraq, so much of it is functioning. You're down to hot spots," he said.

Cantwell said congressional Democrats are holding the administration accountable for progress in Iraq and have presented plans for a possible drawdown of U.S. troops. Republicans, she said, offer no alternatives and simply follow the course set by Bush.

"He's for staying the course," Cantwell said of McGavick. "I'm for standing up in the U.S. Senate and saying we need to change course."

For months, Cantwell has refused to reconsider her 2002 vote approving the invasion. Told last week that McGavick would have opposed the invasion had he known what he knows today, she seemed to tweak her position, saying: "I certainly wouldn't have voted that way if we knew you could contain Saddam Hussein and we didn't have to worry about what he was going to do."

Cantwell recently voted for a measure to ban permanent military bases in Iraq. McGavick disagreed, saying it was premature to decide.

While both candidates said the Iraqis need to take control of their political destiny, neither is able to articulate a clear position if the security situation remains unstable a year from now.

"Year of transition"

Cantwell said she viewed the brewing conflict with Iraq after the Sept. 11, 2001, terrorist attacks through the prism of her earlier experience in Congress, when she served in the House from 1993 to 1995.

At the time, the Clinton administration struggled to enforce U.N. resolutions against Saddam after the Gulf War, and the Iraqi leader proved hostile and uncooperative.

In October 2002, before she cast her vote to authorize force against Iraq, Cantwell said on the Senate floor: "If military action is eventually taken by a U.N.-backed effort or multinational U.S. effort, that military action would not be a pre-emptive strike, but the enforcement of the Iraqi government cease-fire agreement. ... Saddam Hussein is a global menace that we cannot simply wish away."

In the nearly four years since, Cantwell has voted on dozens of measures relating to Iraq, and her record is almost identical to that of Democratic Sen. Patty Murray, who opposed the war resolution. Most of the bills related to military spending. Several, including a defeated measure to raise taxes to pay for military operations, split the Senate between Democrats and Republicans.

Cantwell repeatedly has called 2006 the "year of transition" when security should be turned over to the Iraqis, but she is sketchy on what she would do if violence continues unabated into next year.

"If we get into 2007, and something says sectarian violence has increased, then you might have a different question and a different equation," she said.

Although Cantwell rejected a call by Sen. John Kerry, D-Mass., to remove all troops by July 1, 2007, she backed a resolution that urged Bush to begin a "phased redeployment" of troops by the end of this year, but did not set a deadline for complete withdrawal.

The measure failed 60-39. McGavick said that if he were in the Senate, he would have opposed it.

"I just found the thing was a false choice we will debate loudly and go home and campaign on, but it doesn't change anything," he said.

McGavick handled military and defense matters when he worked as an aide to then-Sen. Slade Gorton, R-Wash., in the early 1980s.

McGavick said the intelligence failure leading up to the Iraq invasion was "embarrassing and injurious to our reputation, and that makes it a big deal."

And he seemed to reject Bush's oft-repeated contention that the Iraq war made America safer by attracting terrorists to a foreign country.

"I wouldn't view it that the objective was to create an attractive nuisance to the terrorists of the world," McGavick said.

No major differences?

Until Congress debated the resolution for a phased redeployment in June, McGavick was saying there were no significant differences between him and Cantwell over Iraq.

Like Cantwell, McGavick would have voted to authorize force in 2002, given the information presented to Congress. And McGavick agreed with Cantwell's votes to continue funding military operations. Both reject specific timetables for withdrawal.

As for articulating a future Iraq policy if the current level of violence continues, McGavick is equally as vague.

"I'm still hopeful that we'll see progress by the end of the year. [If not] then we're going to have a real full discussion about exactly how it is we're going to measure progress and how we're going to have our troops committed relative to that progress. You might wind up with a lot less congressional support for just continuing 'as is' if you don't see real progress."

State Democrats contend McGavick is trying to blur the distinction between him and Cantwell to distract voters from his stance on the war.

Stuart Elway, director of The Elway Poll, said Cantwell's and McGavick's positions are "almost identical," but the poll shows warning signs for both candidates.

McGavick should be concerned about hewing too closely to the White House position on Iraq, Elway said. Only 66 percent of those who identified themselves as Republican agreed with Bush that U.S. troops should remain until the Iraqis can take over security.

On the other hand, he said, the large number of Democrats who advocate immediate withdrawal should give Cantwell pause.

"When you look at the numbers, the person talking about leaving [Iraq] has the advantage, but it's not a strong advantage," he said. "That explains why there is a stalemate about what to do."

Alex Fryer: 206-464-8124 or afryer@seattletimes.com