Immigrant-rights activists on Thursday lamented the U.S. Senate's failure to move forward on immigration reform, calling it "a moral failure for our nation."

Los Angeles Mayor Antonio Villaraigosa, who traveled to Washington this week to lobby in favor of immigration legislation, called the Senate's action "a big disappointment."

"I think that from the beginning we understood there was opposition, primarily from Republicans but also from some Democrats," he said. "I believe that our absolute priority has to be to secure our borders and provide a pathway to citizenship for some 12 million undocumented workers. Some 70 percent of America agrees with that general concept. Unfortunately the Senate rejected it."

Pro-immigration activists called the Senate's failure a defeat that is likely to end any hope of action being taken on the issue until after next year's presidential election.

"This morning, the Senate failed the American people by not moving forward the debate on immigration reform," said Angelica Salas, executive director of Coalition for Humane Immigrant Rights of Los Angeles.

"Our elected representatives are effectively saying to the American public that they are throwing their hands up into the air and refusing to deliver on their promise to fix our broken immigration system," he said.

"Our elected leaders -- people who are supposed to stand up on behalf of Americans -- were bullied by a small contingent of hate-mongering anti-immigrants completely unrepresentative of the larger American public, which continues to call for just, humane and effective solutions," Salas said.

Provisions of the still-born bill would have given illegal immigrants a way to achieve legal status if certain requirements were met, including paying fines and fees, passing background checks and proving proficiency in English. The bill also called for tougher border and work-site security provisions.

Senator Barbara Boxer, a Democrat from California who supported the bill, said she hopes efforts will continue to address the immigration issue.

"As we move forward, I hope that the Senate will work to immediately pass the non-controversial pieces of this bill, such as increased funding for border security," Boxer said. "We also need to legislate a fair way to deal with the 12 million undocumented workers who have become an important part of California's economy and the economy of the country."

Cardinal Roger Mahony of the Roman Catholic Diocese of Los Angeles said the nation's immigration system "remains broken."

"Without reform, our current system will continue to permit the exploitation of workers, the separation of families and will handicap efforts to secure our nation's borders," he said. "Each day that this status quo is permitted to exist is a moral failure for our nation, as well as a legislative one."

Dolores Huerta, co-founder of the United Farm Workers union, said that until an immigration bill is passed, immigrants would continue to live in fear.

"Our people are living in terror right now, you know, getting people knocking at the doors in the middle of the night, taking parents away, leaving the children with citizenship behind," she said. "This cannot go on. It's got to be stopped."

But not everyone was disappointed by the Senate's action.

"This was a tremendous victory for the American people," said Ira Mehlman of the Federation for American Immigration Reform. "The public really interjected itself into this debate and made it very clear to the White House and the Senate that they would not sit by quietly while their interests were being sold out."

"This is the second time that this bill has had to be killed off and we hope that this time the Senate gets the idea that the American public rejects the whole idea," he said. "They don't need any legislation to enforce the laws that they already have on the books."

Mehlman urged the federal government to work on securing the borders and cracking down on employers who hire illegal immigrants.