WASHINGTON —  Sen. Richard Lugar, R-Ind., a senior Republican and a reliable vote for President Bush on the war, said Monday that Bush's Iraq strategy was not working and that the U.S. should downsize the military's role.

The unusually blunt assessment deals a political blow to Bush, who has relied heavily on GOP support to stave off anti-war legislation.

It also comes as a surprise. Most Republicans have said they were willing to wait until September to see if Bush's recently ordered troop buildup in Iraq was working.

"In my judgment, the costs and risks of continuing down the current path outweigh the potential benefits that might be achieved," Lugar, R-Ind., said in a Senate floor speech. "Persisting indefinitely with the surge strategy will delay policy adjustments that have a better chance of protecting our vital interests over the long term."

Only a few Republicans have broken ranks and called for a change in course or embraced Democratic proposals ordering troops home by a certain date. As the top Republican and former chairman of the Senate Foreign Relations Committee, Lugar's critique could provide political cover for more Republicans wanting to challenge Bush on the war.

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Lugar's spokesman Andy Fisher said the senator wanted to express his concerns publicly before Bush reviews his Iraq strategy in September.

"They've known his position on this for quite a while," Fisher said of the White House.

However, Fisher said the speech does not mean Lugar would switch his vote on the war or embrace Democratic measures setting a deadline for troop withdrawals.

In January, Lugar voted against a resolution opposing the troop buildup, contending that the nonbinding measure would have no practical effect. In spring, he voted against a Democratic bill that would have triggered troop withdrawals by Oct. 1 with the goal of completing the pull out in six months.

Next month, Senate Majority Leader Harry Reid, D-Nev., plans to force votes on several anti-war proposals as amendments to a 2008 defense policy bill. Members will decide whether to cut off money for combat, demand troop withdrawals start in four months, restrict the length of combat tours and rescind Congress' 2002 authorization of Iraqi invasion.

Expected to fall short of the 60 votes needed in the Senate to pass controversial legislation, the proposals are intended to increase pressure on Bush and play up to voters frustrated with the war.

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