The US Senate, after a decade of trying and failing, has passed a wide-ranging immigration bill that would put 11 million foreigners now living illegally in the United States on a path to American citizenship.
The bill, which is backed by President Barack Obama, would invest $46bn in new funding to increase border security and revamp the US visa system.
"Now is the time when opponents will try their hardest to pull this bipartisan effort apart so they can stop common sense reform from becoming a reality. We cannot let that happen,'' Obama said in a statement shortly after the vote on Thursday.
The Senate voted 68-32 for the bill, giving more than two-thirds support in the 100-member chamber. Earlier, backers said they were pushing to get 70 votes to help sway the more conservative House to consider it.
But it faces strong opposition in the House of Representatives, where many Republicans oppose giving legal status and eventual citizenship to the 11 million.
The developments marked an end to years of partisan gridlock on immigration, and a small bipartisan group of senators had worked out the current bill.
"Do the right thing for America and for your party," said Senator Bob Menendez, a Democrat. "Find common ground. Lean away from the extremes. Opt for reason and govern with us."
The legislation's chief provisions include numerous steps to prevent future illegal immigration and to check the legal status of job applicants already living in the US.
At the same time, it offers a 13-year path to citizenship to as many as 11 million immigrants now living in the country illegally.
The measure also requires 20,000 new Border Patrol agents, the completion of 1,226km of fencing and the deployment of an array of high-tech devices along the US-Mexico border.
Other provisions would expand the number of visas available 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.
In addition, the system of legal immigration that has been in effect for decades would be changed, making family ties less of a factor and elevating the importance of education, job skills and relative youth.
The Republican leader of the House, Speaker John Boehner, said at a news conference the separate legislation his chamber considers will have majority support among Republicans.
Boehner declined to say if there were circumstances under which he could support a pathway to citizenship, but he made clear that securing the border was a priority.