House Rules Committee Chairman Pete Sessions (R-Tex.), left, and Rep. Tom Cole (R-Okla.), the panel’s vice chair, listen to arguments from committee chairs on March 22 as the panel meets to shape the final version of the Republican health-care bill before it goes to the House floor. (J. Scott Applewhite/AP)

As members of the House Freedom Caucus elbowed past reporters to enter their Wednesday meeting, a slim backpack-toting man slipped in almost unnoticed. He was Michael Cannon, director of health-policy studies at the libertarian Cato Institute, and he was offering some advice on why Republicans’ American Health Care Act needed to die. A chart-packed three-page memo, given to every member, warned that passage would mean the GOP would absorb “blame for the ongoing collapse” of Affordable Care Act exchanges, split the right (“the left will be motivated”) and “risk single-payer” after Republicans lost.

“Why would they take that bullet?” Cannon said after leaving the meeting.

As some Republicans consider whether to smother the AHCA, they’ve gotten regular and robust backup from the right’s major policy institutions. Heritage Action for America, which Republican leaders quietly (and sometimes less quietly) accuse of needing opposition to exist, has refused to budge on the bill and announced Wednesday that it would “score” a vote for it, counting it against a member’s rating. FreedomWorks, which organized a rally against the bill a week ago, has also continued to campaign against it.

And on Tuesday evening, Freedom Partners — hub of the political network backed by billionaire industrialists Charles and David Koch — sent out a new denunciation of the AHCA. “The AHCA in its current form fails to fully repeal Obamacare and would lead to even higher costs and fewer choices for Americans,” said policy director Nathan Nascimento. “We want to work with Congress and the White House on finding solutions that reduce costs and increase access to quality care for all Americans, but that can’t happen without first repealing Obamacare — and this bill does not do that. Absent major changes, the AHCA will fail to deliver relief for Americans, and we’ll stand with principled lawmakers who recognize this and vote against it.”

There are conservative supporters of the AHCA. Antiabortion groups have endorsed the bill, which would defund Planned Parenthood, despite some concerns about whether the Senate’s rules will allow that.

Americans for Tax Reform (ATR) has gone all in for the bill, reiterating its support after Republicans tried to attract more votes by advancing its tax cuts. “The more tax relief we get now, the easier it is to do fundamental tax reform later in the year — both from a tax policy and a tax revenue baseline perspective,” wrote the group’s Ryan Ellis after the bill was updated. “Cutting the capital gains rate into the teens is a lot easier when you start at 20 percent than when you start at 23.8 percent.”

But Americans for Tax Reform is at odds with groups that often share its foxhole. The Club for Growth, which continues to oppose the AHCA, is out with ads in swing states warning that “Ryancare” would amount to “doubling down on disaster” and keeping everything voters hated about the ACA. On Wednesday, ATR spokesman John Kartch asked (in vain) for the Club to explain why its ad insisted that the AHCA kept the ACA’s tax hikes.

The Club for Growth, along with Heritage Action, FreedomWorks, the Tea Party Patriots and Americans for Prosperity, participated in a newsy face-to-face meeting with President Trump about the AHCA. Since that meeting, none of the invited groups have backed the bill; AFP is now pledging to run ads thanking members who oppose the AHCA, blunting ads from the American Action Network — an ally of House Speaker Paul D. Ryan (R-Wis.) — that have told voters that “President Trump is 100 percent behind” the bill.