WASHINGTON (AP) – Republicans on Wednesday cleared procedural hurdles in the House and Senate on the way to giving President Bush authority to detain, interrogate and try terrorism detainees before military commissions.

House Republicans succeeded on a vote in blocking any Democratic amendments to the legislation. In the Senate, Republican leaders won an agreement from Democrats to debate the bill for less than a dozen hours and then vote on it.

Four Democrats and Republican Senator Specter are being given opportunities to offer amendments in the Senate, but all were expected to fall with lawmakers eager to adjourn this weekend to devote the next five weeks to campaigning for re-election.

Mr. Specter’s amendment would strike a provision in the bill that denies terrorism suspects the right to appeal their detention in court.

Senate Majority Leader Bill Frist urged quick action on the overall detainee legislation.

“Until Congress passes this legislation, terrorists … cannot be tried for war crimes in the United States and the United States risks fighting a blind war without adequate intelligence,” Mr. Frist said. “That’s simply unacceptable.”

While bowing to the inevitable, Democrats continued to criticize the bill. Senator Levin, the senior Democrat on the Senate Armed Services Committee, said defendants still won’t be able to confront some classified evidence against them while allowing evidence obtained through torture.

Rep. Ike Skelton of Missouri, top Democrat on the House Armed Services Committee, said Congress was acting in “an election-year frenzy” without addressing human rights and constitutional issues raised by the bill.

“I predict that the system created by this bill will be successfully challenged in the courts,” Mr. Skelton said. “Our nation cannot afford to have any terrorist convictions overturned on judicial appeal.”

Debate on the bill began almost simultaneously on both sides of the Capitol after hours behind-closed-doors negotiations. The House was expected to pass it by late afternoon and the Senate could complete late Wednesday night or Thursday.

That would get it to Mr. Bush by week’s end, giving Republicans an anti-terrorism victory to brag about on the campaign trail.

“Time is of the essence,” said Rep. Tom Cole, R-Okla. “We must move this legislation to the president’s desk.”

However, Mr. Bush and Republican lawmakers will have to settle for less than a full loaf of the anti-terror measures they had hoped to enact before the Nov. 7 elections.

Mr. Bush wanted Congress to pass separate legislation that would have authorized warrantless surveillance of international communications of terror suspects, as well as the separate plan to establish a court system to prosecute terrorists.

But as lawmakers scurried to finish several items before leaving town this weekend and focus instead on midterm elections, Mr. Bush’s terrorism surveillance bill fell to the wayside. Vast differences between House and Senate versions of the wiretapping bill cannot be bridged before week’s end, Republican officials conceded.

That allowed Republicans to focus on passing a bill that would allow Mr. Bush to put the nation’s most dangerous terror suspects on trial this fall – just as voters head to the polls.

The legislation would establish a court system to prosecute terror suspects, after the Supreme Court had ruled in June that Mr. Bush needed Congress’ blessing to do so. And while the bill would grant defendants more legal rights than they had under the old system, it nevertheless would permit some trial evidence not usually allowed in regular courts.

Hearsay evidence, for example, would be permitted, as long as a judge finds it to be reliable. Coerced testimony would be allowed in narrow circumstances – generally if a judge finds it reliable and the statement was taken before a 2005 ban on cruel, inhuman or degrading treatment.

The bill provides extensive definitions of war crimes such as torture, rape and biological experiments – provisions intended to protect CIA interrogators from being prosecuted for war crimes when handling terror suspects.

Mr. Bush wanted a provision that would have said America interprets Geneva Convention standards to mean that cruel, inhuman or degrading treatment cannot be used. Republican senators balked at this request because they said it would “redefine” the 1949 treaty.

But senators did agree to add language that says the president can “interpret the meaning and application” of the treaty. While he would not be allowed to authorized interrogation techniques that would violate prohibited war crimes, he would be allowed to decide whether interrogation techniques are within bounds.