WASHINGTON ― House Republicans are finally within striking distance on their health care bill, flipping at least two members through a small amendment and shoring up support among some undecided members through good old-fashioned whipping. But GOP leadership faces the same problem they’ve had all along: They’re still short the votes, and putting the bill on the floor now and trying to eke out passage could be disastrous if the vote doesn’t go Speaker Paul Ryan’s (R-Wis.) way.

Republicans may vote this week anyway, after former Energy and Commerce Chairman Fred Upton (R-Mich.) and Energy and Commerce member Billy Long (R-Mo.) worked out an amendment adding $8 billion over five years for states that waive Affordable Care Act protections for people with pre-existing conditions. While it initially looked like that money would go to the high-risk pools that states would have to set up as a condition of opting out of those provisions, it now looks like it will be a separate fund, though details have not been released.

Either way, it’s a truly paltry sum compared to what most experts believe is needed to make something like a high-risk pool work for sick people. The Center for American Progress estimated on Tuesday that the current GOP bill underfunds the high-risk pools by $200 billion over 10 years. That’s why it looks like the amendment has only flipped Upton and Long at this point, though it could provide some cover to other undecided members who always wanted to be on the leadership’s team.

GOP whips ― most notably, Chief Deputy Whip Patrick McHenry (R-N.C.) and Majority Whip Steve Scalise (R-La.) ― have been feverishly working the House floor this week, hearing out wavering members and working out deals where, if Republicans were just a couple votes short, lawmakers would vote yes.

That means that if the bill passes, the margin may only be one or two votes. But if it fails, the total could look much worse.

Republicans need 217 votes on the bill if all members vote, meaning they could lose 22 of their members and still pass the legislation. That 217 threshold could be lowered if some members are absent ― or if leadership could convince a fence-sitter to just not show up. But leadership believes they can’t go to the floor unless they’re within a few votes. Based on the HuffPost whip count, it looks like Republicans are right around the number they need.

Even if the bill gets out of the House, however, the current legislation would face a tough time in the Senate, where Republicans have already spoken out about concerns over the $880 billion Medicaid cut that the House is proposing. The provisions weakening protections for people with pre-existing conditions also look unlikely to survive that chamber, meaning this entire bill may be an exercise in handing Democrats attack ads in 2018.

Leaders are eying a Thursday vote, but they could push back a one-week recess into the weekend, or even into next week, if they think that gets them closer to moving the bill out of the House. Republicans will be voting without a Congressional Budget Office score on the latest iteration of the legislation, after it was changed dramatically by an amendment from moderate Tom MacArthur (R-N.J) and Freedom Caucus Chairman Mark Meadows (R-N.C.) to allow states to opt out of those popular pre-existing condition protections. That, miraculously, doesn’t seem to be giving many members pause.

Leadership could also add additional amendments to pick off a member here or there, and they still have plenty of money to dole out to win over reluctant moderates. The last CBO score projected that the bill would save $150 billion over 10 years, but that figure could now be potentially much lower depending on how many people use the tax credits that the bill would establish to help people purchase insurance.

There’s a sense among some members now that Republicans are so close to passing the bill that they won’t stop tweaking the legislation and offering members side-deals for their votes until they get there. The only problem is that there is still a largely dedicated base of about a 18 centrist Republicans who don’t look like they’re getting closer to yes.

That’s fine for leaders, as long as they don’t lose any of the members leaning against the bill or who are still undecided. But again, it’s tight.

Here is the current HuffPost whip count on the latest version of the GOP health care proposal. This whip count is based on conversations with lawmakers and staffers with knowledge of how members are voting. Not every lawmaker on this list has confirmed how he or she will vote ― this is our best guess: No (16)

Mark Amodei (Nev.)

Andy Biggs (Ariz.)

Barbara Comstock (Va.)

Ryan Costello (Pa.)

Charlie Dent (Pa.)

Dan Donovan (N.Y.)

Brian Fitzpatrick (Pa.)

Jaime Herrera Beutler (Wash.)

Walter Jones (N.C.)

John Katko (N.Y.)

Leonard Lance (N.J.)

Frank LoBiondo (N.J.)

Thomas Massie (Ky.)

Patrick Meehan (Pa.)

Ileana Ros-Lehtinen (Fla.)

Chris Smith (N.J.) Lean No (8)

Paul Cook (Calif.)

Jeff Denham (Calif.)

Mario Diaz-Balart (Fla.)

David Joyce (Ohio)

Michael Turner (Ohio)

David Valadao (Calif.)

Daniel Webster (Fla.)

David Young (Iowa) Undecided (13)

Justin Amash (Mich.)

Carlos Curbelo (Fla.)

John Faso (N.Y.)

Darrell Issa (Calif.)

Steve Knight (Calif.)

Erik Paulsen (Minn.)

Bruce Poliquin (Maine)

Peter Roskam (Ill.)

Ed Royce (Calif.)

Elise Stefanik (N.Y.)

Rob Wittman (Va.)

Kevin Yoder (Kan.)

Don Young (Alaska) Lean Yes (17)

Rod Blum (Iowa)

Ted Budd (N.C.)

Bradley Byrne (Ala.)

Mike Coffman (Colo.)

Rick Crawford (Ark.)

Tom Emmer (Minn.)

Jeff Fortenberry (Neb.)

Rodney Frelinghuysen (N.J.)

Garret Graves (La.)

Peter King (N.Y.)

Adam Kinzinger (Ill.)

David McKinley (W.V.)

Dave Reichert (Wash.)

Hal Rogers (Ky.)

Scott Tipton (Colo.)

Glenn Thompson (Pa.)

Lee Zeldin (N.Y.)