(CNN) Thursday is a critical day for both the future of hundreds of thousands young undocumented immigrants and House Republican leadership, as an insurrection led by Republican moderates is about five signatures away from forcing a House vote.

What's called a discharge petition -- a rare procedural move that bypasses the committee and leadership process to put a bill directly on the floor (more on that below) -- is that close to reaching the number of Republicans that would be needed, assuming all Democrats sign on as well. A floor vote on a series of immigration bills would likely result in the passage of a bill that would offer DACA recipients a path to citizenship along with a package of border security funding and policy changes.

The effort has gotten so close that it is spooking leadership and conservatives, who are seeking ways to fight back that only further put pressure on House leadership.

This is where the immigration battle is as of Thursday:

What is going on?

The House could be forced to vote on a range of bills covering immigration policy including a proposal dealing with DACA recipients, giving them a path to citizenship along as well as giving money for border security.

Who's forcing the vote?

A group of moderate House Republicans who are facing midterm election-related pressure to act on immigration.

How can they force a vote?

Moderate Republicans are using a rarely-used and rarely-successful procedural maneuver called a "discharge petition." Stick with me: A discharge petition forces a vote by the whole House of Representatives on specific bill or bills. In this specific instance, this petition would force a vote as early as June on four different immigration plans. This would bypass going through committee and whole array of other roadblocks Republicans leaders could typically use to stop legislation they don't like.

How real is this threat?

At this point, moderates are just a handful of signatures away -- five Republicans to be exact, assuming all Democrats in the House also sign it -- from being able bypass the committee process and leadership and force a vote on a package of immigration bills on the floor.

Are all House Democrats on board?

Whether House Minority Leader Nancy Pelosi can deliver all 193 members of her conference seems a bit ambitious. On Thursday morning, she said at her weekly news conference that "99%" of her caucus is on board. At least one -- Rep. Filemon Vela of Texas -- has expressed concerns about border enforcement measures in his border district. The more Democrats don't sign the petition, the more Republicans would have to come up with additional signatures.

According to a Democratic member familiar with the DACA discharge petition efforts, Democrats have been given the clear sign to start signing the petition and are expected to start doing so in large numbers Thursday.

Wait -- why are Republicans fighting with each other? I thought they were in control of the House.

Moderates are tired of being promised a vote they still haven't had and it's moderates who feel like their jobs will be on the line in November if they don't do something. Rep. Mike Coffman, a moderate with a large Latino population in Colorado, said for example he's just tired of being patient.

This is a big deal because Republican leadership in the House is finally having to reckon with immigration, an issue that deeply divides their party and could become a liability for them in the midterms.

Are more Republicans going to sign up?

Though DACA discharge petition leaders have been visible walking the floor during votes, they haven't been clearly whipping for signatures. According to a source familiar with the moderates' efforts, their whipping operation is intentionally low key and out of public view, so as not to signal to their opponents who to go after to whip against them.

What are Republican leaders doing about this?

House Speaker Paul Ryan reiterated Thursday his disapproval of the discharge petition, saying during a news conference it's "futile" and that none of the proposed bills will get a presidential signature.

Ryan and his leadership team that includes two men vying to replace him, are stuck in the middle -- struggling to deal with the growing frustration of their moderate members who are tired of being told to wait for him to figure out the issue, and also dealing with threats from the conservative right flank that could tank an unrelated farm bill in their effort to stop the DACA push from the center.

Those Republican leaders have been emphatic that a discharge petition is a bad idea for the conference with six months to go until the midterms and that passing a moderate immigration bill could depress base turnout. They are actively whipping against it. During a conference Wednesday, Ryan and House Majority Leader Kevin McCarthy -- who wants to replace Ryan when he retires in January -- both spoke to this point.

According to a person familiar and a member in the room, McCarthy's message was put down your phones and listen because a discharge petition is not the way we should be legislating. The source said that McCarthy told the conference that discharge petitions hurt the conference and that is the last thing we should be doing right now before the elections.

Moderates insisted last night after their meeting with leadership that they were not backing down. Ringleader Jeff Denham, a California Republican, has pledged he has the votes all along.

All leadership will say is that "conversations continue."

So what's wrong with a couple of votes? Why does leadership care?

The way the votes would work is that whatever bill got the most votes would advance and that's likely to be a more moderate proposal than Republicans want. As CNN has repeatedly reported, it would likely result in the passage of a bill that would offer DACA recipients a path to citizenship along with a package of border security. This kind of procedure gives Democrats much more power than they typically have on the floor in a Republican-controlled House.

What about Trump?

It was notable that McCarthy and Ryan went to the White House on Tuesday to talk immigration. The fact is the only way to stop the discharge petition may be to come up quickly with an alternative bill that has the President's blessing. But the sticking points that existed a few months ago have not gone away and trying to nail down exactly what the White House will accept has proved challenging to say the least.

Ryan's message has been that the conversations continue, but as one aide put it to me it is not as if they have some finished bill they have just been waiting to unveil for this kind of moment. There is real work to be done.

A senior White House official told CNN's Sarah Westwood the White House has had conversations directly with Denham, Curbelo and Virginia Rep. Bob Goodlatte about the discharge petition, as well as with leadership.

The White House is opposed to the discharge petition and does not want it to move forward. But the senior White House official said cracking down on signatures is something "leadership needs to take ownership of, more so than us."

Another source said White House aides, including legislative affairs director Marc Short, have worked with leadership to try to stop the petition and work on a possible alternative plan, one that would incorporate the four pillars plan the White House tried to roll out months ago. But no one seems to see a real path forward for any kind of immigration legislation right now, especially not in the Senate.

At his weekly news conference Thursday, Ryan also defended the President's demands on immigration, saying he's been "extremely reasonable" in his prior requests and indicated the President hasn't made any changes in his demands since his bill failed to advance in the Senate earlier this year.

This story will be updated.