WASHINGTON — Some activists against illegal immigration were quick to claim a jubilant victory after a Senate bill stalled that would have put millions of undocumented immigrants on a pathway to citizenship.

But while it may be off the Senate floor for now, Commerce Secretary Carlos M. Gutierrez and Homeland Security Secretary Michael Chertoff — whose departments would each be greatly affected by the bill — said Friday that they are optimistic the proposals will be back sooner rather than later.

"I think we are literally two to three days short of finishing a momentous bill," Chertoff said. "This is one of the biggest pieces of legislation I've seen since I've been an adult. If it takes a couple extra days so be it."

Sen. Majority Leader Harry Reid, D-Nev., pulled the bill late Thursday when senators failed in a 45-50 vote to gain the 60 votes needed to end debate and move to a vote.

Gutierrez said he is still optimistic a bill will be back, based on floor remarks Thursday by Reid and Senate Republican Leader Mitch McConnell, R-Ky., who said they wanted to bring the bill back to the floor. He doubts they would say such a thing if they did not mean it.

"We are going to reach out with the facts and with the logic and make the case that this is a bill in our national interest," Gutierrez said. "We believe that we will get a majority of votes — there may be some that we will never get — but we're going to keep trying to get every single vote that we can."

During a teleconference Friday, representatives of groups that support the bill expressed their frustration over the vote but predicted the bill would be back. Tom Snyder, national political director of UNITE HERE, attributed the bill's failure to "poison pills" tossed by a small minority.

"It's going to take leadership, very firm leadership, now to get this over the finish line," he said.

Only six Republicans voted to end debate on the bill. However, opposition didn't only come from conservatives who disliked its proposed "Z-visa" for undocumented immigrants to achieve legal status if they meet certain requirements such as paying a $5,000 fine.

Eleven Democrats voted with Republicans against ending debate on the bill, which has also been criticized by some labor unions and advocates for immigrant rights because of its shift away from family reunification visas and its proposed temporary guest worker program for unskilled workers with no pathway to permanent residency.

Sens. Orrin Hatch and Bob Bennett, both R-Utah, were among those who voted against Thursday's motion.