AFL-CIO President Rich Trumka attacked the deal sharply as "anti-worker," although he also made clear organized labor would continue to support the overall legislation.
Robert Hoffman, senior vice president for government affairs at the Information Technology Industry Council, welcomed the deal. "We obviously want to keep moving the bill forward and building support for the legislation, and this agreement allows us to do so," he said.
The issue of same-sex spouses hovered in the background from the start, and as the committee neared the end of its work, officials said Leahy had been informed that both the White House and Senate Democrats hoped he would not risk the destruction of months of painstaking work by putting the issue to a vote.
"There have been 300 amendments. Why shouldn't we have one more?" he told reporters at one point, hours before called the committee into session for a final time to debate the legislation.
A few hours later, Republicans and Democrats both answered his question bluntly.
"This would fracture the coalition. I could not support the bill," said Sen. Lindsey Graham, R-S.C., who was a member of the bipartisan so-called Gang of Eight that drafted the core elements of the bill.
Republicans and Democrats alike also noted that the Supreme Court may soon issue a ruling that renders the controversy moot.
Despite the concern that bipartisan support for the legislation was fragile, there was no doubting the command over committee proceedings that backers held.
In a final reminder, an attempt by Sen. Ted Cruz., R-Texas, to delete the pathway to citizenship failed on a 13-5 vote.
In defeat, he and others said they, too, wanted to overhaul immigration law, but not the way that drafters of the legislation had done.
Sen. Charles Grassley, R-Iowa, recalled that he had voted to give "amnesty" to those in the country illegally in 1986, the last time Congress took a major look at immigration. He said that bill, like the current one, promised to crack down on illegal immigration, but said it had failed to do so.
The centerpiece provision of the legislation allows an estimated 11 million people living in the U.S. illegally to obtain "registered provisional immigrant status" six months after enactment if certain conditions are also met.
Applicants must have arrived in the United States before Dec. 31, 2011, and maintained continuous physical presence, must not have a felony conviction of more than two misdemeanors on their record, and pay a $500 fine.
The registered provisional immigrant status lasts six years and is renewable for another $500. After a decade, though, individuals could seek a green card and lawful permanent resident status if they are up to date on their taxes and pay a $1,000 fine and meet other conditions.
Individuals brought to the country as youths would be able to apply for green cards in five years.
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