With President Donald Trump’s self-imposed July 4 deadline looming, Senate Majority Leader John Thune is racing against time to push through the administration’s sprawling tax and spending bill.

The legislation, a $4.5 trillion tax-cut behemoth paired with $1.2 trillion in spending reductions, has ignited a firestorm of dissent among Republicans, leaving Thune with a razor-thin margin to secure passage. The South Dakotan, a veteran of Capitol Hill’s toughest fights, can lose no more than three of his 53 GOP senators, with Vice President JD Vance on standby to cast a tie-breaking vote. But as the clock ticks, roughly eight Republican senators are digging in their heels, and the fissures within the party threaten to sink Trump’s flagship policy.

Trump isn’t making it easier. The president, ever the provocateur, has taken to Truth Social to blast dissenters, zeroing in on Senators Thom Tillis of North Carolina and Rand Paul of Kentucky after both voted against a procedural motion late Saturday to advance the bill. “Tillis—a talker and complainer, NOT A DOER!” Trump raged in one post, vowing to back a primary challenge against the outgoing senator. Paul, meanwhile, drew fire for his fiscal hawk stance against the bill’s $5 trillion debt ceiling hike. With Tillis unshackled by his decision to forgo reelection and Paul unmoved by Trump’s taunts, Thune’s path to 50 votes looks increasingly treacherous.

Public sentiment isn’t helping. A Pew Research poll shows 49% of Americans oppose the bill, with just 29% in favor and 21% undecided. The numbers reflect the divisive stakes: massive tax relief for workers and businesses on one hand, steep cuts to programs like Medicaid on the other. Republicans broadly back the tax cuts—extensions of the 2017 reforms, plus new breaks for tipped workers, seniors, and car buyers—but the spending reductions have sparked a civil war within the caucus.

A Party Divided: Hawks vs. Moderates

The Senate’s GOP fracture lines are stark. Fiscal conservatives like Wisconsin’s Ron Johnson, Florida’s Rick Scott, Utah’s Mike Lee, and Wyoming’s Cynthia Lummis are pushing for deeper cuts, particularly to Medicaid. Johnson, a longtime deficit hawk, is spearheading an amendment—slated for a marathon voting session starting late Sunday—to accelerate reductions in health coverage, arguing the bill’s current $1.2 trillion in savings doesn’t go far enough. “We’re still piling on debt,” he warned on Fox News last week. “This is a chance to show we’re serious.”

But moderates like Susan Collins of Maine, Lisa Murkowski of Alaska, and Tillis are sounding the alarm. They point to Congressional Budget Office estimates that the bill could strip insurance from 11.8 million Americans over a decade—a political third rail as the 2026 midterms approach. Collins, ever the voice of caution, has called the Medicaid cuts “a bridge too far,” while Murkowski and Tillis are fighting to preserve renewable energy credits vital to their states’ economies. Alaska’s wind and solar jobs, and North Carolina’s clean-tech sector, hang in the balance.

The clash has turned compromise into a high-wire act. Thune must bridge the gap between Johnson’s austerity push and the moderates’ pleas for restraint—all while Trump demands speed over specifics. “Get it done by July 4th!” the president barked online, a directive that leaves little room for the painstaking dealmaking needed. If Thune pulls it off, the Senate could pass the bill by Monday after an overnight vote-a-thon. Then it’s up to House Speaker Mike Johnson to ram the unchanged package through a restive lower chamber—a tall order given grumbling from House Republicans over the Senate’s handiwork.

Economic Stakes: Boom or Bust?

Beyond the political maelstrom, the bill’s economic footprint looms large.

The $4.5 trillion in tax cuts aim to juice growth by flooding cash into households and businesses. The White House touts an average $10,000 annual boost in take-home pay for working- and middle-class families, with standout provisions like a 15% tax cut for those earning $30,000 to $80,000, and zero taxes on overtime and tips—saving affected workers nearly $2,000 a year. Seniors get historic breaks, and car buyers score deductions for American-made vehicles.

Small businesses, a GOP sacred cow, stand to gain big. The bill doubles the expensing limit for equipment and property costs to $2.5 million and locks in a permanent, enhanced small business tax deduction. Full expensing for new factories and machinery, plus a renewed Opportunity Zones program promising $100 billion for rural and distressed areas, round out the “America First” pitch.

Yet the $1.2 trillion in spending cuts cast a shadow. Slashing Medicaid could kneecap state budgets and widen inequality, economists warn, potentially negating the tax-cut windfall. The $5 trillion debt ceiling increase—a necessity to keep the government solvent—has fiscal hawks like Paul crying foul, arguing it undercuts the bill’s thrift. Sectors like healthcare and renewable energy face uncertainty, while small businesses reliant on stable consumer spending could feel the pinch if millions lose coverage.

The White House’s Hard Sell

Undeterred, the administration is pitching the bill as a populist triumph. “The One Big Beautiful Bill delivers the largest tax cut for working- and middle-class Americans in history,” the White House proclaimed, promising a “Blue-Collar BOOM.” Beyond the paycheck boosts, it highlights family-friendly perks: a beefed-up Child Tax Credit for 40 million households, permanent paid leave credits, and “Trump Investment Accounts” for newborns. Housing affordability gets a nod with expanded low-income tax credits, while family farms dodge death taxes with a higher exemption.

The messaging is relentless: this is Main Street’s moment. Permanent Opportunity Zones, full expensing for manufacturing, and no tax hikes—the White House casts it as a rejection of Wall Street excess and a lifeline for the heartland. “President Trump’s One Big Beautiful Bill lowers tax rates to keep more money in Americans’ pockets—PREVENTING THE LARGEST TAX HIKE IN HISTORY,” the statement blares, a nod to the looming expiration of the 2017 cuts.

The Verdict Hangs in the Balance

As senators brace for a sleepless Sunday, the bill’s fate rests on Thune’s negotiating chops. Success would hand Trump a legacy-defining win, bolstering his 2028 prospects and proving his dealmaking bona fides. Failure risks a GOP implosion, with Trump’s wrath—and primary threats—waiting in the wings.

The next 48 hours will decide it all. A Senate breakthrough could ripple through the economy for years, reshaping taxes, healthcare, and energy. But if the GOP’s fault lines prove too deep, Trump’s big beautiful vision might collapse under its own weight—leaving Washington, and the nation, to pick up the pieces.