Senate Republicans were expected Monday to drop their filibuster of the defense authorization bill over unrelated energy issues, setting up what could be at least a week of debate on national security, a senior GOP aide said.

The Senate was expected to vote late Monday to limit debate on proceeding to the bill, which it eventually is expected to pass. In a July 31 vote, the Senate fell nine votes short of the 60 needed to limit debate on the motion to proceed, with most Republicans holding firm against moving forward.

There was no agreement yet to limit the number or kind of amendments that can be debated on the bill, the aide said.

Up to now, Republicans have resisted Democratic attempts to limit the debate to germane amendments. That formula would exclude non-defense proposals, such as GOP proposals to lift the ban on offshore oil drilling or Democratic favorites such as an amendment to define as hate crimes offenses motivated by bias based on gender, sexual orientation or disability.

The bill would authorize $612.5 billion for defense programs in the Defense and Energy departments for the fiscal year beginning Oct. 1. That sum includes $70 billion for operations in Iraq and Afghanistan. All funds would have to be appropriated in separate bills.

Though Democrats are not expected to renew the debate about withdrawing troops from Iraq, they may try to add language to require that Congress approve any long-term security agreement between the United States and Iraq. The administration has threatened to veto the House version (HR 5658) of the bill over similar language.

That bill, which the House passed in May, drew veto threats over a wide range of provisions, some of which have counterparts in the Senate version. The White House has yet to weigh in on the Senate bill.

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