The Senate immigration overhaul cleared its final procedural hurdle on Thursday, winning the support of 68 senators as the chamber hurtled toward a final vote on the contentious legislation.
The Senate voted 68-32 to end debate on the bill, teeing up a vote on final passage later in the afternoon. Senate Majority Leader Harry Reid has called for a 4 p.m. ET vote.
The legislation faces an uncertain fate in the House, where majority Republicans are drafting their own bills and have voiced opposition to the Senate version.
But the vote to cut off debate, which required a minimum of 60 senators to succeed, demonstrated that supporters easily have the votes to approve it in the Senate.
Republican opponents of the bill voiced frustration as the chamber sailed to finalize work on the legislation. Sen. Charles Grassley, R-Iowa, on Wednesday said he felt "used and abused," as he tried to slow down the process and call for more amendments to be considered.
All Democrats, in addition to 14 Republicans, voted for the legislation on Thursday. All "no" votes came from the Republican side of the aisle.
The legislation would be the most sweeping overhaul of America's immigration system since the 1980s. It would legalize millions of presently illegal immigrants, while expanding legal immigration and increasing border security.
"We're on the edge of passing one of the most significant pieces of legislation that this body has passed in a very long time," Sen. Chuck Schumer, D-N.Y., said on the Senate floor Wednesday. "The vast majority of members in this body realize that the immigration system is broken and needs fixing."
But many in the GOP-controlled House oppose the pathway to citizenship at the center of the Senate bill. And many prefer a piecemeal approach rather than a sweeping bill like the one the Senate is producing.
Republicans in both chambers have complained that a late-developing compromise measure that increased spending on border security still put "amnesty" ahead of security.
At its core, the legislation in the Senate includes numerous steps to prevent future illegal immigration, while at the same time it offers a chance at citizenship to the 11 million immigrants now living in the country unlawfully.
It provides for 20,000 new Border Patrol agents, requires the completion of 700 miles of fencing and requires an array of high-tech devices to be deployed to secure the border with Mexico.
Businesses would be required to check on the legal status of prospective employees. Other provisions would expand the number of visas for highly skilled workers relied upon by the technology industry. A separate program would be established for lower-skilled workers, and farm workers would be admitted under a temporary program.
The basic legislation was drafted by four Democrats and four Republicans who met privately for months to produce a rare bipartisan compromise in a polarized Senate. They fended off unwanted changes in the Senate Judiciary Committee and then were involved in negotiations with Republican Sens. John Hoeven of North Dakota and Bob Corker of Tennessee on a package of tougher border security provisions that swelled support among Republicans.
Outnumbered critics insist the bill falls short of the promises made for it.
Sen. Richard Shelby, R-Ala., called it "the mother of all amnesties."
The House Judiciary Committee is in the midst of a piece-by-piece effort, signing off Wednesday on legislation to establish a system requiring all employers within two years to check their workers' legal status.
The Judiciary Committee was turning its attention Thursday to a bill on high-skilled workers. Last week it approved two more measures, one on agriculture workers and a second to make illegal presence in the country a federal crime, instead of a civil offense as it is now.
The Associated Press contributed to this report.