The committee's first meeting to consider the amendments is Thursday morning, and there will be plenty to think about: committee members have filed 300 amendments to the 844-page bill.
Such amendments could destabilize the delicate compromise reached by the four Republican Senators and four Democratic Senators who crafted the bill, as well as the agreement reached by the AFL-CIO and the U.S. Chamber of Commerce behind the scenes.
The Republican amendments outnumber the Democrats' almost 2 to 1, with 194 filed by the right side of the aisle, compared to 106 from the left side.
Senator Chuck Grassley (R-Iowa) alone filed 77 amendments.
The strongest amendments call for beefing up border security. Republican lawmakers said the border needs to be more secure than what the plan calls for.
The Senate’s plan calls for boosting enforcement along parts of the the border to a 90 percent success rate, meaning agents would catch or chase back to Mexico most of the people trying to come in illegally. Some Republicans now say they’re not convinced with the definition of that 90 percent benchmark.
"That sounds like a way to set up a good excuse not to vote for immigration reform,” said Tony Payan, a political analyst with the Baker Institute.
As The Associated Press reports, a major point to watch is how the four Gang of Eight senators who are in the committee will react to the amendments.
The Judiciary Committee includes four of the eight senators who authored the bill, and they plan to try to vote together in the committee to stave off poison pill amendments from either side that could upend their deal.
However, as of Tuesday afternoon these lawmakers -- Democrats Chuck Schumer of New York and Dick Durbin of Illinois, and Republicans Lindsey Graham of South Carolina and Jeff Flake of Arizona -- had not decided how to proceed on all issues.
Two of the most notable amendments from the Democratic side come from Sen. Patrick Leahy (D-Vt.). They would allow gay and lesbian U.S. citizens to sponsor their partners for residency the way straight couples can. One amendment would allow U.S. citizens to petition for "permanent partners" and not just spouses to gain U.S. residency. Another calls for all legal marriages to be recognized by federal immigration law, which would include same-sex marriages.
Some Republicans have warned that such an amendment would kill immigration reform.
Other amendments called for strengthening northern border security and pushing forward the date by which immigrants would have had to have entered the country illegally to be eligible for a path to citizenship.