The 49-48 vote came two weeks after the Senate, also by a one-vote margin, rejected the same amendment by Sen. Byron Dorgan. The North Dakota Democrat says immigrants take many jobs Americans could fill.
The reversal dismayed backers of the immigration bill, which is supported by President Bush but loathed by many conservatives. Business interests and their congressional allies were already angry that the temporary worker program had been cut in half from its original 400,000-person-a-year target.
A five-year sunset, they said, could knock the legs from the precarious bipartisan coalition aligned with the White House. The Dorgan amendment "is a tremendous problem, but it's correctable," said Sen. Arlen Specter, R-Pa. The coalition will try as early as Thursday to persuade at least one senator to help reverse the outcome yet again, he said.
Until the Dorgan vote was tallied, Specter and other leaders of the so-called "grand bargain" on immigration had enjoyed a fairly good day.
They had turned back a bid to reduce the number of illegal immigrants who could gain lawful status. They also defeated an effort to postpone the bill's shift to an emphasis on education and skills among visa applicants as opposed to family connections.
And they fended off an amendment, by Sen. Barack Obama, D-Ill., that would have ended a new point system for those seeking permanent resident "green cards" after five years rather than 14 years.
The Obama amendment as the Illinois Senator and Sen. Lindsey Graham, R-S.C. traded verbal blows which carried into an argument in the hallway.
It would undercut "everybody over here who's walked the plank and told our base, 'You're wrong,"' Graham said.
Obama briefly appeared stunned and demanded time to respond. The notion that his amendment would gut the bill "is simply disingenuous" he said. "It's engaging in the sort of histrionics that is entirely inappropriate for this debate."
All three amendments were seen as potentially fatal blows to the bill, which would tighten borders, hike penalties for those who hire illegals and give many of the country's estimated 12 million illegal immigrants a pathway to legal status.
The Senate voted 51-46 to reject a proposal by Sen. John Cornyn, R-Texas, to bar criminals — including those ordered by judges to be deported — from gaining legal status. Democrats siphoned support from Cornyn's proposal by winning adoption, 66-32, of a rival version that would bar a more limited set of criminals, including certain gang members and sex offenders, from gaining legalization.
Sen. John McCain, R-Ariz., alone among his party's presidential aspirants in backing the immigration measure, opposed Cornyn's bid and backed the Democratic alternative offered by Sen. Edward M. Kennedy, D-Mass.
Senators also rejected a proposal by Robert Menendez, D-N.J., that would have delayed the bill's shift in favor of attracting foreign workers with needed skills as opposed to keeping families together. Menendez won 53 votes, seven short of the 60 needed under a Senate procedural rule invoked by his opponents.
Menendez's proposal would have allowed more than 800,000 people who had applied for permanent legal status by the beginning of 2007 to obtain green cards based purely on their family connections — a preference the bill ends for most relatives who got in line after May 2005.
Meanwhile, Sen. Hillary R. Clinton, D-N.Y., fell short in her bid to remove limits on visas for the spouses and minor children of immigrants with permanent resident status.
While several Cornyn amendments failed, he prevailed on one matter opposed by the grand bargainers. That amendment, adopted 57 to 39, would make it easier to locate and deport illegal immigrants whose visa applications are rejected.
The bill would have barred law enforcement agencies from seeing applications for so-called Z visas, which can lead to citizenship if granted. Cornyn said legal authorities should know if applicants have criminal records that would warrant their deportation.
Opponents said eligible applicants might be afraid to file applications if they believe they are connected to deportation actions. Sen. Dianne Feinstein, D-Calif., said in an interview that Cornyn's amendment was "not a deal-killer" but would have to be changed in House-Senate negotiations.