The Associated Press on Saturday obtained details of the deal that includes $1.6 billion for structures including a wall for border security.
The agreement between three Republican and three Democratic senators would prevent deportation of hundreds of thousands of so-called Dreamers, who were brought to this country as children and are here illegally.
President Donald Trump and some GOP congressional leaders have said the bipartisan deal is insufficient. Its proponents - led by Sens. Dick Durbin, D-Ill., and Lindsey Graham, R-S.C. - say they are continuing to round up supporters in hopes of building momentum for their plan.
Political battle lines intensified following Trump's vulgar description of African nations and derogatory comments about Haiti at a White House meeting last Thursday, and its fate is uncertain.
A showdown was expected by Friday, the deadline for Congress approving a spending bill to prevent a government shutdown the following day. Some Democrats are threatening to withhold needed votes for the budget measure unless there's an immigration accord.
Some details of the bipartisan Senate compromise:
Twelve-year pathway to citizenship. Can be reduced by up to two years for time in U.S. under the Deferred Action for Childhood Arrivals program, the Obama-era initiative Trump wants to terminate.
Once Dreamers become citizens, they would not be able to sponsor their parents to also become citizens. Parents would qualify for three-year work permits, which could be renewed repeatedly.
$1.6 billion for designing and building structures including a wall. That's the same amount Trump requested for this year to build or replace 74 miles of fencing in Texas and California.
Additional $1.1 billion surveillance technology, retaining and relocating Border Patrol agents.
Other steps including body cameras, rescue beacons, more investigators for Border Patrol.
Lottery distributes up to 50,000 for visas annually to people from countries that send few immigrants to the U.S. It is a major entry way for people from African nations.
Instead, half those visas would go to people from "priority countries" with low rates of immigration to the U.S. Priority to applicants under a "merit-based" system. Documents did not define what those terms mean.
Other half of the visas would go to people currently receiving temporary protected status. It gives several hundred thousand people from countries struggling with natural disasters or armed conflicts the right to live and work in the U.S. Trump has curtailed it for people from El Salvador, Haiti, Sudan and Nicaragua.
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