The modern congressional whip operation shifted into high gear this week as House Republican leaders scrambled to find support for their plan to overhaul the health-care system.

But House Speaker Paul D. Ryan (R-Wis.) does not have the tools that previous speakers once used to win over recalcitrants before cliffhanger votes.

For some of these lawmakers, the health bill would be a lot easier to digest with a side of pork — some earmarked funding to show they deliver for their district. But earmarks were banished by Ryan’s predecessor, John A. Boehner (R-Ohio), with Ryan’s support, when Republicans took charge in 2011.

Additionally, the old promise of political support for casting tough votes doesn’t carry the same weight. One key bloc of voters Ryan needs, the moderates, mostly comes from districts where President Trump lost to Democrat Hillary Clinton in 2016. These Republicans see political separation from Trump as their path to survival in 2018. Offers from the president to appear in their districts or host fundraisers are virtually worthless.

As a result, Ryan is in the same predicament that Boehner had been in during his five years as speaker: trying to pass the most conservative bill possible without losing too many moderates — with the far right balking that the measure still wouldn’t go far enough.

(Bastien Inzaurralde,Sarah Parnass,Jenny Starrs/The Washington Post)

Ryan’s only real tools are fiddling with the policy inside the legislation, and as Ryan and Trump learned the hard way Thursday, that’s never an easy task. After a day of shuttle diplomacy, Ryan and Trump still lacked the votes to approve what has previously been an easy rite of baptism in Republican circles: the repeal of Obamacare.

The day began with Trump hosting members of the conservative Freedom Caucus in the White House to hear their pitch to shift the legislation dramatically to the right, trying to wipe out insurance guarantees for such coverage as maternity care. Before that meeting could even reach its inconclusive finish, moderates had already rebelled.

Reps. Charlie Dent (Pa.), Frank A. LoBiondo (N.J.) and Christopher H. Smith (N.J.) joined a growing list of Republicans from the Mid-Atlantic and Midwest who announced their opposition. Unlike some moderates, these three are all safely ensconced in their districts and face no political worry back home.

One by one, they each subtly made the same proclamation: The current Affordable Care Act might be a mess, but it’s better than Ryan’s proposed mix that would leave 24 million more uninsured by 2026 and those with insurance getting worse coverage.

The moderate Tuesday Group, which Dent chairs, reiterated this message to Ryan’s leadership team at an early afternoon meeting.

By 5 p.m., the roles had switched: Conservatives shuttled into Ryan’s office, while moderates headed to the White House.

And then the entire House Republican Conference convened around 7 p.m. to try to hash out the family feud between two voting blocs that — with about several dozen members of the Freedom Caucus and several dozen in the Tuesday Group — both have the power to blow up the deal.

View Graphic How health care amendments appease GOP moderates and hard-liners

In the end, it was all to no avail, as the planned vote on the critical legislation was delayed until Friday.

[Trump to GOP critics of health-care bill: ‘I’m gonna come after you’]

The recurring message, from the president and the speaker, has been that the GOP team has to stick together. While not perfect, this bill would impale the ACA, setting up momentum for more pieces to replace the health law and on tax cuts.

But Ryan and his team are dealing with newcomers who are unswayed by calls for loyalty. During a series of unrelated votes Wednesday, as his lieutenants scurried across the chamber in search of support for the health bill, the speaker spent about 10 minutes with a few junior members, including Rep. Warren Davidson (R-Ohio), who replaced Boehner after he was run out of Congress in October 2015 by the Freedom Caucus.

What was Davidson’s first act after he was sworn in to Boehner’s southwestern Ohio seat? He joined the Freedom Caucus. Now, he is supporting the changes that the group is trying to add to Ryan’s American Health Care Act.

Formally, Ryan’s team had called Thursday “go time,” vowing to hold the vote whether it was headed for victory or defeat. “I think probably what’s happening is, it’s starting to really sink in to people that we are going to have a vote tomorrow,” Rep. Richard Hudson (R-N.C.), a member of the whip team, said Wednesday.

But the rank-and-file Republicans called Ryan’s bluff, and just as Boehner did many times before him, he pulled the bill from consideration Thursday. He canceled his weekly Thursday conference and made a brief appearance to formally announce that the vote would come Friday.

With no carrots to offer lawmakers, today’s leaders still have some sticks — Trump seemed to joke Tuesday in a meeting with House Republicans that he would not support their 2018 reelection bids if they oppose him.

However, for those staunch conservatives worried about a Trump-inspired primary challenge, there’s a different force that might neutralize any benefit of keeping the president happy. A pair of conservative groups with ties to the industrialist Koch brothers, who oppose the bill’s current makeup, announced Wednesday night that they will throw significant financial support behind Republicans who defy Ryan and Trump.

The other form of punishment — removing rebels from prized committee assignments — also has its drawbacks. House Majority Leader Kevin McCarthy (R-Calif.) led the effort four years ago to boot a handful of antagonists off key panels, only to see those lawmakers become heroes in right-wing media circles.

In 2015, when McCarthy was the heir to succeed Boehner, those once-punished Republicans led the rebellion to block McCarthy’s promotion.

[Can Paul Ryan pull this off, or is he headed for a brutal defeat?]

All this has left Ryan and Trump’s advisers trying to tinker with policy provisions, all too aware that each tick to the right or left has a recurring echo that loses votes from the opposite ideological wing of the caucus.

Ultimately, the whip team tried to make an existential argument to find the final votes to win Thursday’s expected vote: Republicans have been saying they would repeal the Affordable Care Act for seven years, and if they don’t do that now, it will be a political disaster for the GOP and leave in place a law they despise.

“The future of our Republican Party in Congress — and the welfare of generations of Americans and their health care — is on the line,” Hudson said, adding how the stars aligned, finally, with a Republican Congress and president. “The American people gave us this opportunity, and shame on us if we squander this opportunity.”

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