House leaders may need the president to make an aggressive push for the legislation for it to have a chance at passage. Trump plans to meet on Tuesday with the party’s team of vote-counters—a signal that he may engage in the legislative process more directly than he has so far. And the administration issued a letter of endorsement from Tom Price, the secretary of health and human services, and dispatched Mick Mulvaney, the budget director, to talk up the proposal on television. Both Price and Mulvaney are former congressmen who remain close with conservatives in the House, and the White House is banking on their ability to sell the plan to skeptical lawmakers. Yet despite their backing, the House Freedom Caucus, along with Paul and Senator Mike Lee of Utah, announced they would hold a press conference Tuesday afternoon, where they are expected to criticize the bill and call for a vote on a clean repeal of Obamacare.

Two House committees announced plans to mark up and vote on the bill on Wednesday, less than 48 hours after its introduction and, in all likelihood, before the Congressional Budget Office has a chance to fully review it and project its impact on the deficit and the number of Americans who will gain or lose health insurance.

As expected, Democrats immediately assailed the GOP bill as a plan that would strip insurance from people who gained coverage under Obamacare, cut taxes for the wealthy, and reduce funding for Medicaid. “This Republican bill will do massive damage to millions of families across the nation,” House Minority Leader Nancy Pelosi said. “Republicans have decided that affordable health care should be the privilege of the wealthy, not the right of every family in America.”

House Speaker Paul Ryan has told Republicans he wants to pass the health-care bill within three weeks, but whether it ever makes it to a floor vote is an open question. The House effort nearly suffered a mortal blow hours before the plan was unveiled, when four Republican senators—Rob Portman of Ohio, Cory Gardner of Colorado, Shelley Moore Capito of West Virginia, and Lisa Murkowski of Alaska—warned that the emerging proposal would strip insurance from millions of their constituents who gained coverage through the Medicaid expansion. “The February 10th draft proposal from the House does not meet the test of stability for individuals currently enrolled in the program,” the senators wrote in a letter to Majority Leader Mitch McConnell, “and we will not support a plan that does not include stability for Medicaid expansion populations or flexibility for states.”

Republicans have just a 52–48 majority in the Senate, so the loss of four votes would doom any legislation. Paul appears to be a hard “no” on the bill, and several other senators have voiced concerns. Capito told Bloomberg News on Monday night that the new House bill was “moving in the right direction” on Medicaid, indicating that her vote was not lost.

GOP leaders can find a narrow path to passage if enough of their members simultaneously accept legislation that falls short of full repeal while embracing the argument that more consumer choices, lower taxes, and less government involvement is worth the tradeoff of covering fewer people. If the initial reactions are any indication, however, that middle ground may not be large enough to hold a congressional majority.

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