GOP defections from the failed Iraq war policy of President George W. Bush increased Thursday with Rep. Christopher Shays, locked in a tough re-election fight against an anti-war challenger, saying the U.S. should consider setting a timeline for troop withdrawals from Iraq.

“Our troops cannot be there indefinitely,” Shays, R-Conn., said Thursday from London during a telephone conference call with reporters after visiting Iraq for the 14th time since the 2003 U.S.-led invasion. “We need to have a sense of when our troops can withdraw.”

Shays, who has previously opposed timetables for drawing down troops, said he hopes to offer a specific time frame after he holds congressional hearings on Iraq next month.

“We should be able to tell the American people what kind of timeline we can have to begin to draw down our troops,” he said. “It may be a timeline the American people don’t want to hear. It may not be something that brings them out quickly.”

Shays has come under fire for his support of the Iraq war from Democratic challenger Diane Farrell in a race widely seen as a showdown on the war.

Farrell, former Westport First Selectman, took sharp aim at her opponent.

“I don’t think Chris needed to go to Iraq 14 times to know it’s a mess,” she said. “To have a time line, there needs to be an exit plan. There’s no exit strategy.”

Farrell, who opposes troop pullback timetables proposed by some in her party, has called for Defense Secretary Donald Rumsfeld’s resignation in favor of a successor who can develop an Iraq exit plan that Congress supports.

“Congress ought to demand an exit plan,” she said.

The race, one of the most closely watched in the nation, is a rematch of the close contest Farrell lost two years ago.

Anti-war sentiment in Connecticut helped Democrat Ned Lamont topple three-term incumbent Sen. Joe Lieberman, D-Conn., in their primary this month. Lieberman is an independent candidate for re-election.

Shays, seeking an 11th term, denied he was caving in to public sentiment on the war.

“Joe and I have had the same view about this war from basically day one,” Shays said. “His view has not changed because of his election … nor has my view changed because of his election.”

A timeline would help prod Iraqis to move more quickly to take control of their country, he said.

Americans need to be reassured that the U.S. presence in Iraq is “not an open checkbook” that Iraqis “can just draw on ad infinitum,”, Shays said. At the same time, he said, Iraqis must know the U.S. will not leave prematurely.

Shays also had sharp words for Rumsfeld.

“I haven’t had faith in the secretary for a long time,” he said. “I believe huge mistakes were made in disbanding the (Iraqi) army, the police and the border patrol.”

Shays, who is chairman of the House Government Reform subcommittee on national security, emerging threats and international relations, plans hearings to help develop a time line for pulling out troops.

He said a time line would encourage Iraqis to move more quickly in taking control of security and other vital areas. Others have warned that time lines for troop withdrawals would only encourage Iraqi insurgents to wait out U.S. forces.

“It’s not a timeline of when the war ends,” Shays said. “It’s a timeline on when the bulk, not all, but the bulk of the heavy lifting is in the hands of the Iraqis.”

Shays said that despite mistakes in Iraq, the U.S. and its allies must follow through with their promises to stabilize the country.

The congressman said earlier this year that he regrets failing to be more aggressive in overseeing the Pentagon’s Iraq war plan, particularly on cost estimates.

(Andrew Miga of The Associated Press contributed parts of this story)