Must-pass legislation that wraps up the bulk of the remaining congressional agenda besides health care was expected to easily clear a Senate hurdle in the wee hours of Friday.
Anchored by a $626 billion Pentagon funding bill, the measure also carries short-term extensions of unemployment benefits, highway and transit funding, key pieces of the anti-terror Patriot Act and prevents doctors from shouldering a 21 percent cut in Medicare payments.
The timing of the post-midnight vote — which would defeat GOP stalling tactics and force a final vote to clear the bill for President Barack Obama on Saturday morning — has been governed more by the brawl over health care than significant opposition to the defense measure or its additional baggage.
Republicans are using every avenue available to them to try to delay or kill the health care legislation, including stretching out debate on the defense measure. It passed the House Wednesday by an overwhelming 395-34 vote.
The underlying defense measure provides $626 billion to the Defense Department for the budget year that began almost three months ago, a 4 percent increase for core Pentagon operations.
It includes $128 billion for military operations in Iraq and Afghanistan.
The president has yet to request funds for his recently announced troop increase in Afghanistan, and there is no money in the bill for that.
A stopgap funding measure expires at midnight on Friday, but White House budget director Peter Orszag has advised Senate leaders that no funding lapse would occur so long as Congress delivers the bill to Obama on Saturday.
The package contains about $465 million to develop an alternative engine for the F-35 Joint Strike Fighter, the Air Force's multimission fighter of the future. The administration said in June it would veto the legislation if it would "seriously disrupt" the F-35 program, an iffy threat at best. It has since backpedaled from the veto threat.
The bill contains no funds for new F-22 fighters. Defense Secretary Robert Gates staked his reputation on killing the program, which has its origins in the Cold War era but is poorly suited for anti-insurgent battles in Iraq and Afghanistan.
The measure also trims personnel and maintenance accounts from previous versions of the measure to pump up weapons procurement for Afghanistan and Iraq by almost $2 billion.
The defense measure would trim $900 million from the Pentagon's $7.5 billion budget to train Afghan security forces. It would use the money to buy about 1,400 additional mine-resistance vehicles suited for rugged conditions in Afghanistan. Lawmakers say the training program can't absorb that much money in the coming year, so they used it for other purposes.