A surprising midnight Senate vote has rocked Washington after eighteen Republican senators broke with their party to back a push for higher taxes on America’s wealthiest earners. The vote came as lawmakers worked through the night to advance President Trump’s “big, beautiful” tax and immigration bill, with the amendment ultimately failing but revealing fractures inside the GOP at a crucial moment.

The amendment, pushed by Sen. Susan Collins (R-ME), sought to let Trump’s 2017 tax cuts expire for billionaires and ultra-wealthy households earning over $25 million per year, raising the top income tax rate from 37% back to 39.6%. While 17 other Republicans backed Collins, the measure was soundly defeated in a 22-78 vote, with most Democrats opposing it for not going far enough and many Republicans opposing any tax increases while the economy remains fragile.

Sen. Collins, facing re-election in 2026, argued the billionaire tax hike was needed to double funding for rural hospitals, a key concern in her home state. “If there are a lot of amendments accepted, that could make a difference,” Collins said, signaling she remains undecided on Trump’s broader bill.

Sen. Lisa Murkowski (R-AK), another frequent swing vote, joined Collins and echoed concerns over rural healthcare funding, while also hinting she could withhold support for Trump’s package unless additional changes are made.

The move came despite President Trump’s public caution against raising taxes, warning Republicans that even a small increase could become a weapon for the left to attack the party during the 2026 midterms. “Republicans should probably not do it, but I’m OK if they do,” Trump posted on Truth Social, signaling ambivalence while defending his original tax cuts.

Fiscal conservative groups blasted the vote. Club for Growth called Collins’ proposal a “poison pill,” warning it would fulfill “Kamala Harris’ tax dreams” and undermine the economic momentum under Trump’s policies.

Critics note the tax increase would have had a limited reach, as many billionaires structure their income through capital gains and dividends, largely shielding themselves from higher wage income taxes. Still, the symbolism of Republicans joining Democrats to push a billionaire tax hike sent shockwaves through conservative circles, with grassroots groups warning it could damage trust heading into the midterms.

The failed amendment reflects deeper tensions within the GOP as Trump’s second-term agenda moves forward. While some Republicans seek targeted revenue increases to address specific funding concerns, others argue that any tax hikes risk fracturing the party and alienating core voters who expect the GOP to protect them from the left’s tax-and-spend agenda.

As the Senate prepares for final votes on Trump’s “big, beautiful” bill, the split on billionaire taxes has left many asking: Will Republicans hold the line on taxes, or are cracks starting to show?

Trump’s allies warn that if Republicans cave now, the media and the Democrats will use it as an invitation for bigger, broader tax increases down the road, while conservatives continue to argue that real growth and American prosperity come from keeping taxes low, even for the wealthy.

Stay tuned—this tax fight is far from over.