Republicans are grappling with how to develop a conservative-friendly Deferred Action for Childhood Arrivals program — the Obama-era order protecting an estimated 800,000 unauthorized immigrants from deportation that President Donald Trump plans to sunset in March.

This week, three Republican senators introduced a bill that is emerging as the Republican-led solution to their DACA problem: a proposal that would create a 15-year path to citizenship for DACA recipients, would have a “merit-based” residency program for children who arrived in the United States before the age of 16, and wouldn’t allow recipients to sponsor family members to the United States on a green card — a direct nod to Trump’s recent calls against “chain migration.”

But already the proposal has undergone a flanking attack from the both the Republican Party’s most conservative members who decry any path to citizenship as “amnesty,” and from Democrats — at least eight of whom have to sign on to any legislative fix in the Senate — who argue the proposal’s age cutoffs are too severe.

It’s clear Congress still hasn’t figured out exactly what they will do about DACA. We know the broad contours of what a deal could look like after top Democratic leaders Nancy Pelosi and Chuck Schumer met with Trump in the White House earlier this month — something that enshrines DACA into law and also has a strong border security package, most likely not including the wall.

But after a week preoccupied by NFL protests, Republicans resurrecting the specter of Obamacare repeal, and a new push on tax reform, what to do about the 800,000 or so young immigrants who grew up thinking of themselves as American has more or less fallen off the national radar.

If a deal does come together, there is a growing list of proposals Republicans and Democrats can choose from.

Four proposals Congress could use to replace DACA

Trump has repeatedly stated he wants DREAMers — those protected under DACA — to stay, and for Congress to figure out something fast. He hasn’t given many more specifics.

His articulation of some hypothetical legislative fix is something that has “massive border security,” doesn’t include amnesty, and will not allow for chain migration, the notion that people will bring in their families once they are eligible for residency. All of those points are up for debate.

Here are some of the interpretations:

The SUCCEED Act, the newest proposal from Sens. Thom Tillis (NC), James Lankford (OK), and Orrin Hatch (UT), appears to address some of these concerns.

Similar to the RAC (Recognizing America’s Children) Act proposal from House Republicans, this would allow people who arrived before the age of 16 and before June 12, 2012, and who have undergone a thorough criminal background check and submitted biometric information, to receive “conditional permanent resident” status — requiring them to work, go to school, or serve in the military. Recipients have to renew this temporary status after five years, and after 10 years they can apply for a permanent residency or a green card.

Green card holders have to wait another five years before they can apply for citizenship. In other words, at a minimum any path to citizenship would take 15 years. Under this proposal, parents of recipients cannot receive any benefits and cannot be sponsored for residency.

Already immigration advocates have decried the bill as too harsh. Sen. Dick Durbin (D-IL) said the proposal would have difficulty picking up Democratic votes. And conservatives haves said the proposal’s path to citizenship — even though it takes 15 years — is equivalent to amnesty. But it’s likely this is a proposal most rank-and-file Republicans can get behind.

As Vox’s Dara Lind has explained, there are the three other options available to Congress:

The BRIDGE Act is the most conservative proposal on the table so far. It’s basically a congressional equivalent of DACA: It would allow the people who met the requirements of DACA to be protected from deportation and work legally in the US for the next three years. The logic behind the bill is to give Congress three years to work out a more permanent solution on immigration — in that sense, it’s basically just a longer version of the six-month deadline Trump has set Congress before people start losing DACA protections en masse. The bill doesn’t have a ton of support. But one of its sponsors, Rep. Mike Coffman (R-CO), is committed enough to it that he’s planning to try a discharge petition (a rarely-successful procedural move) to force it to the floor for a vote. The RAC (Recognizing America’s Children) Act is the proposal favored by many Republicans. It would allow people who arrived in the US before age 16 and have been here for at least five years (and meet educational and criminal requirements similar to the ones under DACA) to apply for “conditional” permanent residency — which they could then, after five years, apply to turn into standard green cards and become citizens. But the bill allows the government to kick people out of their legal status if they don’t stay in school or stay employed. The RAC Act was introduced by a group of Republicans with relatively vulnerable seats, but as it became clear that Trump was going to end DACA, it’s attracted the support of Republicans who are more straightforwardly conservative...When Gov. Rick Scott of Florida urged Trump not to leave DACA recipients out in the cold, he endorsed the RAC Act as a solution to the problem. The DREAM Act, in its current incarnation (as opposed to the versions that have been introduced for the past 16 years), would legalize DREAMers in the same way the RAC Act would: by allowing them to become “conditional” permanent residents and then removing the conditions after certain requirements are met. It’s more generous than the RAC Act; it allows anyone to qualify who’s been in the US since age 18 and has lived here for four years, and allows people who have Temporary Protected Status (as well as those who are unauthorized) to apply for conditional permanent status as well. And the DREAM Act doesn’t force immigrants to stay in “conditional” limbo for a particular amount of time; instead, they can get green cards after they’ve been in college for a certain amount of time (or have a degree), or have been employed for at least 75 percent of the time they’ve had a work permit. The DREAM Act is the bill that most Democrats are backing, along with Senate Republicans who are known to favor citizenship for unauthorized immigrants (Sens. Lindsey Graham, John McCain, and Jeff Flake). But it was also the bill endorsed by the Attorney General of Tennessee when he withdrew himself from the threatened lawsuit against DACA on Friday — a sign it might gain support among more conservative members as well.

All of these proposals would likely be paired with some kind of additional security package.

There’s a lot of circular debate over how to make DACA conservative

Conversations on DACA seem to still be in early stages.

Conservatives in the House have started a working group led by Idaho Republican Rep. Raúl Labrador, who is also in a working group with Republican leadership. In the Senate, Tillis and Lankford’s SUCCEED Act was largely welcomed as the conservative alternative to the Democrats’ push for the DREAM Act — but it’s unlikely to garner enough votes on the other side of the aisle to become law on its own.

As Lind writes, “it is unlikely, to say the least, that any of these bills would have 60 votes in the Senate as they exist today — and that Trump would sign a bill that only addressed the DREAMer question.”

What will be in the compromise? Everyone — including Democrats — have said they can agree to some kind of border security package, as long as it’s not funding for the border wall. That could mean anything from boots on the ground to increased surveillance technology. Even Lankford and Tillis, who proposed the SUCCEED Act this week, say their bill should only be part of the proposal to legislatively address DACA.

But there are certain baseline disagreements within the Republican Party that will likely come to a head once debate heats up, none of which have been cleared up by the president — namely what Republicans can reasonably pass as “not amnesty.”

For some, any path to citizenship is a difficult line to cross — especially without a large border security package added on.

“There would have to be a whole lot more than a wall if I were to give amnesty to a whole lot of illegal aliens who are going to take jobs from American citizens and suppress the wages of American citizens by artificially inflating the labor force,” Rep. Mo Brooks (R-AL) said.