On Thursday, senators will begin the process of "marking up" the bipartisan immigration immigration reform bill.
Both Republicans and Democrats on the Senate Judiciary Committee plan to file a litany of amendments that would make significant changes to the legislation. Members of the "Gang of Eight" have said they will mobilize against controversial amendments that could threaten the legislation. But that likely won't stop senators from at least introducing them in committee.
All amendments must be filed by the end of the day on Tuesday. Thus far, only five changes have been introduced. Sen. Mazie Hirono (D-Hawaii), for example, has introduced an amendment that strengthens family unification. (You can track amendments here).
Here are some of the potential amendments you should look out for:
1. Same-sex couples
Senate Judiciary Committee Chairman Patrick Leahy (D-Vt.) is expected to introduce an amendment that would allow American citizens in a same-sex relationship to sponsor their partner for green cards.
The amendment is expected to be one of the most controversial that's considered during the "mark up" process. Some advocates have pressed Democratic leaders to include gay couples in the bill after they were left out by the "Gang of Eight." President Obama has said he would support it.
But Republican "Gang of Eight" members such as Lindsey Graham (S.C.) and Marco Rubio (Fla.) have called the proposal a "poison pill" that could threaten the overall legislation.
2. Republican Slowdown
Media reports indicate that Republican opponents of the bill are planning to introduce a long list of amendments that would change some of the fundamental elements of the legislation.
With the Democrats in the majority in the Senate, these proposals may not get past the Judiciary Committee. But at the very least, they could slow down the process. Several "Gang of Eight" members on both sides of the aisle have said that they would beat back any attempt to fundamentally alter the bill.
Sen. Jeff Sessions (R-Ala.) is considering proposing changes that would restrict the ability of undocumented immigrants who have adjusted their status to obtain public benefits, Politico reports. Sessions may also put forth a proposal that would restrict the future flow of low-skilled immigrant workers, since he has long said that they would depress wage levels and job openings for American citizens.
The New York Times reports that Republican opponents of the bill could "lengthen the timeline" of the pathway to citizenship and make changes to the fragile agreement on low-skilled worker visas crafted by business and labor groups.
And recall that Rubio, a "Gang of Eight" member, has said that border-security provisions need to be strengthened, or the bill will not be able to pass the House.
Sen. Richard Blumenthal (D-Conn.) plans to offer an amendment that would offer a faster track to legal status to undocumented children, otherwise known as "little DREAMers," reports Elise Foley of the Huffington Post.
Under the bill, undocumented immigrants who were brought to the U.S. as minors but are now over the age of 16 already receive a faster track to citizenship than others. But Blumenthal's proposal would reportedly address other undocumented children not covered by the current language.
Blumenthal's proposal appears to have widespread backing from immigrant-rights advocates. But some Republicans who have already objected to existing fast-path for DREAMers would likely object to the change.