Senate Majority Leader Mitch McConnell is about to face alegacy-defining test of whether he can keep his unruly caucus inline to deliver President Donald Trump's coveted goal of“massive tax cuts” in 2017.

He needs 50 of 52 members, and they have a variety of competingdemands. Some want to limit new deficits, while others want todeepest tax cut possible; some prioritize family tax breaks whileothers want to give businesses a boost; some have parochialconcerns while others tend to be notoriously difficult to win onmajor pieces of legislation.

Senate Majority Whip John Cornyn says he wants a floor vote theweek of Nov. 27. That's two weeks away. Here are the factionsMcConnell and his team have to navigate:

The Fiscal Skeptics

The tax plan going before the Senate Finance Committee Mondaywould increase the federal deficit by about $1.5 trillion over thenext decade—before accounting for any economic growth that it mightspur. That complicates the plan's prospects among someRepublicans.

Tennessee's Bob Corker, Arizona's Jeff Flake and Oklahoma'sJames Lankford have all warned against fiscal recklessness in thebill.

Corker says he doesn't want a “penny” in new deficits or he'llvote against the bill. Lankford says it should be revenue-neutralin the first decade and beyond. Both say they're willing to assume“reasonable” economic growth that would cushion the deficitimpact.

After the Senate plan's rollout Thursday, Flake fired a warningshot: “I remain concerned over how the current tax reform proposalswill grow the already staggering national debt,” he said.

Corker and Flake plan to retire next year, freeing them frompolitical pressure to support their party or please GOP donors.

The Senate plan will change, but for now, one analysis says itwould increase the deficit. On Friday, a conservative-leaningpolicy group, the Washington-based Tax Foundation, projected thatplan would boost the deficit $516 billion over a decade, even afterassuming economic growth.

The Businessmen

Georgia's David Perdue is the former CEO of both Reebok andDollar General. South Dakota's Mike Rounds is a former partner foran insurance and real estate firm. For both, the business side ofthe tax plan is paramount.

If any new revenue measures went after businesses to boostoffsets, that could be a problem for them.

So far, Congress's proposal to cut the corporate tax rate to 20%from 35% has gotten the most attention among business provisions.The House bill would deliver that cut next year, but the Senateplan would delay it until 2019. That won't sit well with Perdue,who has said that “delays on tax would damage our economy.”

“We need to have a sense of urgency like never before in orderget this done this year,” he has said of tax cuts.

Rounds said last month that he wants an “equitable” 25% tax ratefor partnerships, limited liability companies and other so-calledpass-through businessesa provision that doesn't include incomelimits on which firms get the low rate.

But the Senate plan would go a different route, providing a17.4% deduction for such businesses' nonwage income. That breakwould not be available to many types of service businesses—exceptfor those whose taxable income falls below $150,000 for jointfilers or $75,000 for all others.

The Cut, Cut, Cut Corps

President Donald Trump is reported to have suggested that thename of the tax legislation should be the “Cut, Cut, Cut” Bill. Hemight find common cause with Pennsylvania's Pat Toomey, Texas's TedCruz and Kentucky's Rand Paul.

All three senators have emphasized that they want the steepestand longest-lasting tax cut possible. Deficits are of less concernto them; they believe Congress should focus on boosting the economyand deal with deficits by cutting spending.

Toomey downplayed the tax plan's estimated $1.5 trillion cost,saying Sunday on NBC's “Meet the Press” that the legislation wouldlead to “greater economic growth, a larger economy, and therefore,more revenue to the federal government.”

Paul, a libertarian purist who's not fond of compromise, hascalled for a tax bill in which “everyone gets a tax cut” —ideally“at least 15% for every taxpayer.” McConnell and other GOP leadershave already said they can't meet that standard, acknowledging thatunder a broad overhaul there will be outliers who see a taxhike.

Cruz last month urged his party to be “unapologetic” for taxcuts, arguing on CNBC that “we should be going much bigger andbolder” than the $1.5 trillion limit.

The Family Guys

Utah's Mike Lee and Florida's Marco Rubio insist their main taxpriority is to double the Child Tax Credit from $1,000 to $2,000.The Senate plan would raise it to $1,650. Both senators say that'snot enough.

“While we are glad to see an increase to the child tax credit,like the House bill, it is simply not enough for working families,”they said in a joint statement. The two senators also want to applythe credit against payroll taxes as well as income taxes.

Simply raising it to $1,650 costs $582 billion over 10 years,according to Congress's Joint Committee on Taxation. Going higherwould only worsen the red ink, unless tax writers find otheroffsetting revenue.

Would Lee and Rubio scuttle a tax bill if they don't get theirway? That's unclear, but they have staked out a position, and anyretreat would come with some political cost.

“The Senate is not going to pass a bill that isn't clearlypro-family,” the pair said in their statement.

The Moderates

Maine's Susan Collins and Alaska's Lisa Murkowski showed they'renot afraid to deal Trump or Republican leaders a devastating defeatthis year when they cast pivotal votes to block an Obamacare repealbill.

Collins has made a few tax-related demands that have alreadybeen met—including no repeal of the estate tax and no increase inthe lowest individual income tax rate of 10%. But she also saidpeople making over $1 million shouldn't get a tax cut, and theSenate proposal would cut the top rate modestly to 38.5% from39.6%.

Murkowski has said little about the tax effort so far, and shetends to be cryptic about her intentions on major legislationbefore casting her vote. Republican leaders gave her an enticementin the budget vehicle for the tax debate: a fast-track vote topermit oil drilling in Alaska's Arctic National WildlifeRefuge.

The Wildcards

Sen. John McCain of Arizona showed his vote can't be taken forgranted with a momentous thumbs-down on the Senate floor thatkilled Obamacare repeal in July. He has a mixed record on taxes,having voted against Republican tax-cut efforts in 2001 and 2003,citing deficit concerns. McCain, 81 and battling brain cancer, hasdemanded a bipartisan process through regular order on a taxoverhaul.

He tweeted Thursday that he's “pleased” with the tax effort sofar. “I've long believed we need to fix our burdensome tax system& am reviewing the Senate bill to ensure it benefits the peopleof #Arizona,” he wrote.

A different kind of maverick is giving Republican leadersheartburn lately, and he's not even a senator—at least not yet.

Roy Moore, the GOP nominee for a Dec. 12 special electionAlabama, is fending off allegations that he had sexual contact witha 14-year-old girl almost four decades ago. The former judge hasdenied those allegations, and others that he pursued dates withthree other teenagers when he was in his 30s.

Recent polls show Moore slipping in the race against DemocratDoug Jones. A loss would cut the GOP's margin for error in half—tojust one senator.

One way to avoid that problem: Get both the House and Senate tohammer out compromise legislation before Moore—or his Democraticopponent—is sworn in.

From: Bloomberg News

Copyright 2018 Bloomberg. All rightsreserved. This material may not be published, broadcast, rewritten,or redistributed.