After a seemingly endless argument over aviation security measures, the Senate finally came together Thursday and passed the bill on a 100-0 vote.

"A few days ago, I think people would have been very skeptical this bill would pass 100-0," said Senate Majority Leader Tom Daschle, D-S.D., immediately after the vote.

Progress on the bill catapulted Thursday after Republicans effectively shelved the most contentious issue holding up the airline safety bill: an amendment offered by Sen. Jean Carnahan, D-Mo., that would have offered $3 billion in relief to laid-off airline workers. 

Several other amendments were then quickly passed, including one by Sen. John Breaux, D-La., to study the use by flight crews of nonlethal weapons to disable would-be hijackers. The Senate also agreed to two amendments to allow pilots to carry firearms and to put airport security under the jurisdiction of the Department of Justice.  It tabled an amendment to raise the retirement age of pilots from 60 to 63.

Supporters of the bill argued that passage would be crucial to restoring public confidence in air travel. 

"People now are disinclined to travel primarily because they are unsure of the safety of the airline industry," said Sen. Jon Kyl, R-Ariz.  The airline industry reported that air passengers last week totaled about 7 million, 3 million less than the same period last year.

The bill, sponsored by Sens. John McCain, R-Ariz., and Ernest Hollings, D-S.C., ranking member and chairman respectively of the Senate Commerce Committee, included many recommendations offered by President Bush.

It authorizes the presence of more air marshals on flights, directs that steps be taken to fortify cockpit doors, increases anti-hijacking training for flight crews, and imposes a $2.50 passenger fee per flight leg to pay for the changes. 

The Senate stumbled over a provision calling for the federalization of employees who screen bags at airport security checkpoints.  The White House and Republicans in the Senate finally agreed on partial federalization — federalizing the employees at the nation's 142 largest airports and giving smaller airports the option of using local or state law enforcement. 

"Mind you me, there's no Swiss cheese approach here," Hollings said, in explaining that the decision to allow state and local law enforcement to manage security at smaller airports.

The House GOP, however, still opposes the federalization issue.  The House has not voted on the bill because of the disagreement.

Rep. Tom DeLay of Texas, the House's third-ranked Republican, said Wednesday he would try to block consideration of the security bill until he got the votes for legislation that would increase federal supervision over screeners but keep them as private employees. 

House Democratic leader Dick Gephardt of Missouri said the threatened delay in a House vote could amount to a "tragic omission of action on our part to take care of these problems." 

Hollings said he was sure the two chambers could come to an agreement but wasn't sure when.  "We don't know exactly, to be candid with you, but it will be done as quickly as possible," he said.

The Senate breakthrough came after the bottleneck was so thick Wednesday that members on both sides reverted to partisan procedural maneuvers that became almost laughable by the end of the day. 

The maneuvering boiled down to an attempt by Daschle to expedite the process by moving to anti-terror legislation while differences over aviation security were worked out off the floor. 

But McCain objected to setting aside the bill. 

Daschle agreed to continue moving forward, starting with the Carnahan amendment. Republicans struck it down on a 56-44 vote after complaining it was not relevant to the underlying bill. 

Daschle said he was disappointed with the vote against Carnahan's amendment. "Today, the Senate missed a chance to help tens of thousands of aviation workers who didn't lose their lives, but who did lose their livelihoods. Sen. Carnahan and others put together a good, fair, affordable, and extremely limited assistance package for aviation workers. I am gravely disapointed we failed to move forward on it.

Senate Minority Leader Trent Lott, R-Miss., said he agreed that relief for workers was important, but it should be debated in another bill.

Terror Tracking Powers Also Close to Passage 

The two chambers also appeared close to passing the anti-terrorism bill that was being taken up in the Senate immediately after passage of the security legislation. 

Daschle got an agreement Wednesday to limit amendments so that the bill could be finished in several hours. 

The House planned to take up its version of the bill Friday. The Bush administration was pressuring the GOP-controlled House to replace its bill with the Senate version. 

Unlike the House anti-terrorism bill, the Senate version had no "sunset clause" regarding new police powers, and included anti-money-laundering legislation requested by the White House. 

Both the House and Senate legislation would expand the FBI's wiretapping authority, impose stronger penalties on those who harbored or financed terrorists and increased punishment for terrorists. 

Fox News' Julie Asher and The Associated Press contributed to this report.