Republicans hoping to jam a last-minute Obamacare repeal plan through the Senate are confronting a rising tide of opposition as health care groups, patient advocates and even some red-state governors join forces against a bill they worry would upend the nation’s health care system.

The wide-ranging backlash threw the GOP’s repeal push into fresh doubt on Tuesday, even as White House officials and Senate Republican leaders insist they are on the verge of winning the 50 votes needed to dismantle Obamacare under a reconciliation bill that expires in two weeks.

Opponents of the proposal co-authored by Sens. Bill Cassidy of Louisiana and Lindsey Graham of South Carolina seized on its plan to overhaul Obamacare’s subsidized insurance and Medicaid expansion and replace those with block grants to the states — a mass restructuring they warned would sow chaos in insurance markets. They panned its new regulatory flexibilities as a backdoor route to undermining key patient protections — including safeguards for those with pre-existing conditions.

And in the biggest blow, several Republican governors urged the GOP to abandon a plan that would force states to swallow potentially billions in funding cuts — and instead to focus on stabilizing Obamacare.

“The Graham-Cassidy bill is not a solution that works for Maryland,” said Maryland Gov. Larry Hogan, one of the half-dozen GOP governors to come out against the bill so far. “We need common-sense, bipartisan solutions that will stabilize markets and actually expand affordable coverage.”

The criticism from Republican governors adds another complication to an already fraught process for Senate Republicans facing a tight deadline to repeal Obamacare. GOP leaders — once skeptical of the Graham-Cassidy plan’s chances — are now all in on a bid to speed it through the Senate.

In a clear bid to boost the bill’s prospects Tuesday, House Speaker Paul Ryan and the White House came out in opposition to a bipartisan plan to stabilize Obamacare being written by Sens. Lamar Alexander (R-Tenn.) and Patty Murray (D-Wash). The intention was to put pressure on Republican senators to back the last-ditch effort to gut Obamacare.

Alexander later announced he’d abandoned work on that effort after failing to find consensus. He has said he’d “like to” be able to support Graham-Cassidy and is still reviewing the bill.

Senate Majority Leader Mitch McConnell also backed the approach Tuesday, although he declined to commit to bring it to the floor.

“We’re in the process of discussing all of this,” McConnell said. “Everybody knows that the opportunity expires at the end of the month.”

All of which has amped up the pressure on GOP lawmakers who are eager to fulfill their seven-year repeal vow but who remain puzzled about what the bill would actually mean for their home states — especially since the Congressional Budget Office said it will not have details about the practical implications of the bill, including how many people could lose coverage and the impact on insurance premiums, “for at least several weeks.”

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