(Bloomberg) -- House tax writers pushed back the reveal oftheir highly guarded, long awaited tax bill by a day, a sign thatdisputes among Republican lawmakers are threatening their effort topass comprehensive legislation by Thanksgiving.

If the bill is released Thursday, one day later than planned,GOP leaders will have just 10 official legislative days before theholiday to do nothing short of rewiring the U.S. economicengine.

To succeed, they must gain the support of a caucus that’sgrumbling about being left in the dark, avoid lobbyists’ attemptsto sidetrack the bill and win House passage on the sort oftimetable that’s usually reserved for emergency legislation.

For Republicans, who failed to deliver on promises to repeal andreplace Obamacare earlier this year, it may already be anemergency.

A chaotic, confusing day of meetings and conflicting statementson Tuesday reflected both hope and anxiety, and raised questionsabout the prospects for swift passage.

Internal GOP strife and frustration led to the delay, accordingto a former House aide who’s familiar with the deliberations.

Pushing back the rollout -- even just a day -- makes it morelikely Republicans will end up passing simple tax cuts instead of atax code revamp, said the former aide who asked not to be namedbecause the discussions were private.

House leaders and White House officials sought to downplay thedelay, saying speedy passage is still possible. But once a billdrops, the task may become vastly more difficult.

“All hell’s going to break loose,” said Senator John Kennedy, aLouisiana Republican. “This is going to have plenty of cheesecake.But it’s going to have plenty of spinach. This is broadening baseand lowering rates.”

Should lawmakers settle for simple cuts to individual andcorporate rates -- measures that would almost certainly have to betemporary under congressional budget rules -- they’ll fall short ofwhat GOP leaders and the Trump administration have promised: aonce-in-a-generation permanent overhaul of the U.S. tax code,similar to what happened in 1986 under former President RonaldReagan.

Still, House Ways and Means Chairman Kevin Brady said he waspleased with the progress committee members had made, and his panelremained on schedule to take action and approve a bill beginningnext week.

SALT issues

Some Republicans took a positive view of the delay. “It suggeststo me they’re really working on it in good faith,” saidRepresentative Frank LoBiondo of New Jersey. “That’s really what Itake out of it.”

GOP lawmakers and tax lobbyists remained confused lateTuesday about key portions of the bill that werethe subject of 11th hour negotiations. Among the uncertaintieswere the status of changes to tax-deferred retirement savingsaccounts, the state and local deduction for individuals, the fateof the estate tax and the schedule for cutting the corporate taxrate from 35 percent to 20 percent.

Representatives of conservative interest groups left a meetingwith House Speaker Paul Ryan on Tuesday afternoon offeringconflicting views on how quickly the 20 percent corporate ratewould be achieved.

Even an announcement of the bill’s release was muddled; theWhite House released a statement saying the delay was no big dealbefore Brady announced the delay. Brady, a Texas Republican, saidtax writers would work through the night Tuesday.

Over the weekend, Brady had bowed to Republican members fromhigh-tax states including New York and New Jersey and agreed topreserve a federal tax break for state and local property-taxpayments. But some Republicans -- including RepresentativeElise Stefanik of New York and Representative Leonard Lance of NewJersey -- said Tuesday evening they weren’t yet satisfied.

Retaining the property tax deduction is “moving in the rightdirection but there are still issues that need to be addressed,Stefanik said.

Representative Peter King of New York questioned “how serious”party leaders were in winning over lawmakers in high-tax stateswith a broad compromise on SALT. Asked if he felt reassured by whathe had heard, he replied, “Not really.”

One of the decisions House writers are said to have finally made-- to keep the top individual income tax rate at 39.6 percent forthose with adjusted gross incomes of about $1 million -- could bemet with resistance from conservative Republicans who want to cutrates for all taxpayers.

‘Bigger picture’

Some of the winners of the eventual bill seem clear --corporations would get a tax cut, and many partnerships andclosely-held businesses would pay a reduced rate of 25 percent. Butthe losers are largely still unknown -- the “special interests”whose tax deductions, credits and other breaks would be reduced oreliminated. Such changes are crucial to limiting the bill’s deficitimpact to just $1.5 trillion over 10 years, the amount required bythe GOP budget.

Once the losers are revealed, their lobbyists and allies willmount an intense campaign to protect them.

“That means some people are going to be unhappy. Some interestgroups are going to be unhappy,” Kennedy said. “But they’ve got tolook at the bigger picture.”

If the legislative calendar and looming lobbying resistanceweren’t tough enough, there’s another source of anxiety for Houseleaders: The Senate plans to operate on a separate track with itsown tax bill -- a prospect that could gum up House efforts.

Top House leaders have privately expressed concerns that someHouse members won’t want to vote for politically difficult measuresthat the Senate’s bill lacks, said two people familiar with thematter. And conversely, one of the people, a senior GOP aide, saidthat if House Republicans see provisions in the Senate bill theylike, they may demand their inclusion in the House version.

Two bills

“I think we’ll probably be on somewhat parallel tracks. If wewaited for the House to get all the way through with it we’dprobably have a hard time” getting it enacted in 2017, SenateRepublican Conference Chair John Thune told reporters Tuesday.

“By the time we start marking up, hopefully they’ll be on thefloor,” he said. “We realize there are going to be, perhaps,differences between the two bills. Our members might like things inthe House bill and theirs might like things in the Senate bill. Butthat’s the process.”

Senator Finance Chair Orrin Hatch intends to release hislegislation “in the coming weeks,” said spokeswoman Julia Lawless.“Details will be released when finalized.”

Other questions remain unanswered about the contents of theHouse bill, even for GOP lawmakers. Brady said Tuesday that hehadn’t finalized where the individual income tax brackets would beset or how much the Child Tax Credit would be raised.

Adding to the onslaught will be Democrats, who are gearing up toblast the Republican bill as a tax hike on the middle class, basedpartly on the GOP call for ending an expensive deduction for statetaxes on income and sales, a move that’d mostly hit high-tax statesthat lean Democratic.

The House Republicans’ bill will “essentially be initiating openwarfare on the middle class,” said Senate Minority Leader ChuckSchumer, a New York Democrat. “Their tax plan double-taxes middleclass Americans to help pay for tax cuts for the rich.”

Work holidays

Speaker Paul Ryan, who’s dead set on shepherding a tax rewritethrough Congress, met with Trump on Tuesday afternoon. The twoRepublicans “agreed on the urgency of helping the middle class byenacting historic tax reform by the end of the year,” said DougAndres, Ryan’s spokesman.

While many obstacles remain, nobody doubts the determination ofmost Republicans to pass a tax bill this year -- especially afterfailing to repeal Obamacare, or build a wall on the Mexican border,or advance an infrastructure package.

“If we need to, we’ll work through Thanksgiving. We’re going toget this done,” Kennedy said. “This business of, well we ran out oftime? That dog doesn’t hunt anymore. We’ll work nights. We’ll workweekends. We’ll work holidays.”

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