(Bloomberg) -- Rishi Sunak was visibly relieved after staving off a rebellion on the right of his Conservative Party to win a vote on his signature immigration policy. The UK prime minister hugged his chief political enforcer in Parliament, and jubilant aides celebrated with whiskey late into Tuesday evening.

Meanwhile right-wing Tory lawmakers turned on each other, fearing they had missed their best chance to bend the legislation to their political will. Sunak’s law is officially about deporting asylum-seekers to Rwanda, yet many rebel MPs see it as a chance to fix what they regard as the missed opportunity of Brexit: asserting Parliament’s supremacy over British judges and international law.

The row has been festering in the governing party for years, amid accusations that post-Brexit arrangements with the European Union squandered freedoms won in the 2016 referendum. Some of the same so-called Brexit Spartans have led the criticism of Sunak’s Rwanda bill, urging the premier to use it to “dis-apply” various international human rights obligations the UK has signed up to.

But Sunak’s victory, by 313 votes to 269 in the House of Commons, casts doubt about the strength of the Tory party’s right fringe, in terms of numbers and their ability to coalesce around a coherent plan.

To be sure, it was a vote Sunak was expected to win. An administration hasn’t lost at the early “second reading” stage of a bill since 1986. Right-wing Tories will have other chances to try to change the law or block it, and the upper House of Lords is likely to have objections that could prevent Sunak beginning deportation flights as planned before a general election expected next year.

Politically, though, members of Sunak’s Cabinet are urging him to take one lesson from the vote: that the Tory right is fundamentally disorganized and not as large, or as powerful, as it claims. Fewer than 30 of them rebelled, short of the 40 to 100 claimed by some of their cohort in briefings before the vote, and even then they only abstained. No Tory MP voted against the bill.

When the legislation returns to the House of Commons in January, those ministers — from the more centrist wing of the party — argue the government should call the rebels’ bluff and offer only the most minor concessions that fall well short of their demand to flout international law.

The question is a live one after Mark Francois, leader of the European Research Group of staunch Brexiteers, said they would seek to amend the government’s legislation and that Sunak had told them before Tuesday’s vote he was willing to harden the bill to get the right-wing Tory MPs onside.

“We will want to continue listening carefully to colleagues,” Sunak’s spokesman, Max Blain, told reporters at a regular briefing on Wednesday, when asked about what the premier had in mind.

But in an interview with the Spectator magazine, Sunak himself dismissed his critics’ tactics over his Rwanda bill as “debating society” behavior.

Sunak should stare down the right once and for all and be confident that rebel lawmakers neither have the numbers to block his bill, nor to remove him from office before the election, a senior minister said, speaking to Bloomberg on condition of anonymity to discuss internal party management. The prime minister should stop worrying about pandering to right-wingers, they said.

Any change should narrowly focus on tightening language around deportees’ right to appeal their cases, one official said. Sunak’s team should take comfort from the fact that the combination of center-right Tory MPs and those right-wingers who are unwilling to bring down the government, appears big enough to see the bill through the Commons, they added.

Some on the Tory right, however, are still threatening to vote down the bill next time round if Sunak doesn’t make significant changes.

Veteran MP Bill Cash, one of the original Tory euroskeptics privately dubbed “Lord Chief Justice Cash” by the ERG, is in charge of drafting what the right sees as a compromise. The aim is to leverage the theory that, if an agreement can’t be reached, the number of abstainers on Tuesday would be enough to sink Sunak’s legislation if they vote against it in January.

But splits have emerged behind the scenes, with some rebels now conceding the government may pass the bill in the Commons with minimal adaptations. The most hardline MPs, including former Home Secretary Suella Braverman and backbenchers Simon Clarke and Jonathan Gullis, spent Tuesday trying to convince colleagues this was the moment of maximum leverage and that they should vote against the bill, people familiar with those conversations said.

At a meeting in Westminster to thrash out a collective position before the vote, they lost the argument. Gullis strode angrily from the room before the discussion was over and Robert Jenrick, the former immigration minister who quit in protest at the legislation last week, also left early.

The direction was clear when ex-premier Liz Truss, seen by colleagues as agitating against Sunak’s leadership, said she would vote for the bill, a person familiar with the talks said. Francois then told reporters the “bulk” of the rebels would abstain.

One rebel MP said it was fantasy to think they would be in a stronger position in January, predicting the government would convince several of the abstainers to vote for the bill. They accused government whips of offering financial incentives to chip away at the opposition. A spokesperson for the chief whip declined to comment. Another rebel said they suspected Sunak would only offer crumbs in terms of any changes.

Other rebels were scathing about the quality of their own operation. One MP suggested they would be better off defecting to the Reform UK party founded by Brexit campaigner Nigel Farage, to properly challenge Sunak. Another called the rebels’ decision to dub themselves the “Five Families” after the New York Mafia — a reference to the various right-wing factions — an embarrassment.

Sunak, buoyed by Tuesday’s result, poked fun at the right-wingers at his weekly Prime Minister’s Questions, telling the Commons that Christmas is “a time for families, and under the Tories we do have a record number of them.”

His problems are far from over, trailing the opposition Labour Party by about 20 points in the polls and still facing significant hurdles to get his Rwanda legislation through Parliament. But Sunak will hope the moment of greatest threat to his premiership — from his own Tory MPs, anyway — has passed.

--With assistance from Joe Mayes and Ellen Milligan.

(Updates with Sunak’s comments to Spectator magazine in 10th paragraph.)

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