Senate Republicans rushed past reporters as they left a Wednesday-evening briefing with House committee chairmen. The meeting, they said, was “positive” and “constructive”—Capitol Hill code for “There is no deal yet.” “It was an interesting discussion” was about all the usually voluble Senator Ted Cruz would say. He added, cryptically, that he thought the talks would continue “for some time.” By Thursday, the Texas conservative had written an op-ed in Politico calling on Republicans to go much further than Ryan’s plan calls for. He wrote that the party should, if needed, overrule the Senate parliamentarian to fully repeal Obamacare’s insurance regulations and mandates. However, the GOP may not be able to do that under the budget reconciliation process, which it is using to roll back the law with a simple majority instead of a filibuster-proof 60 votes.

In the House, Ryan’s biggest problem remains the Freedom Caucus, which, if its three dozen or so members voted as a bloc, could sink the leadership plan. The conservatives’ biggest problem with the bill is its reliance on refundable tax credits, but they’ve also complained about plans to limit the popular tax deduction for health insurance and the lack of a full elimination of Obamacare’s Medicaid expansion. The group’s leaders are aware that Ryan and his team may try to call their bluff, betting that conservatives won’t actually be willing to vote against a repeal bill if it comes up for a vote. The leadership can afford to lose no more than 19 votes to achieve a majority of 218, although the threshold may be slightly lower due to vacancies in the chamber. “I think there would be lots of people afraid to vote no, but I think there would be enough [unafraid] where you couldn’t get to 218,” said Representative Mark Meadows of North Carolina, the Freedom Caucus chairman. Adding to Ryan’s headache, the Koch Industries-backed Americans for Prosperity on Sunday urged Republicans to “go back to the drawing board” after Politico reported that a recent draft contained few changes from the leaked bill that conservatives are opposing.

In addition to conservatives, House leaders must persuade more moderate Republicans to accept a Medicaid compromise that may result in reduced funding—and coverage—in states that expanded the program under Obamacare. “It’s going to be tough,” said Representative Peter King of New York, where, he noted, 800,000 people were newly covered. “We have to get something done, but I have real strong feelings on Medicaid expansion. I didn’t like the concept from the start, but it’s there.”

For all of the GOP’s problems in the House, however, it’s still the Senate that remains the party’s bigger challenge. Senator Rand Paul’s farcical scavenger hunt for the “secret” bill on Thursday and Friday obscured a more worrisome point for party leaders. They cannot count on the votes of Senators Susan Collins of Maine or Lisa Murkowski of Alaska, who opposed a repeal bill in 2015 over its defunding of Planned Parenthood, which is also targeted in the current draft. “There is not a consensus at this point,” Collins said Sunday on Face the Nation. With Republicans holding only 51 votes, Paul’s additional opposition would torpedo the legislation. Cruz and Senator Mike Lee of Utah, who have aligned themselves with the House Freedom Caucus in the past, could be similarly crucial. And other senators, including Lindsey Graham, have warned party leaders against trying to jam them with a take-it-or-leave-it plan that they can’t amend. “I’ll leave it,” Graham warned at a town-hall event on Saturday. The tight margin is one reason Senate Majority Leader Mitch McConnell has been sounding less confident than Ryan about the chances for success in his chamber.

The House speaker remains unbowed. Ryan has not adopted the by-any-means-necessary rhetoric of Pelosi, but he’s crept a bit closer. “I am perfectly confident that when it’s all said and done, we’re going to unify,” he told reporters on Thursday, “because we all, every Republican, ran on repealing and replacing [Obamacare] and we’re going to keep our promises.” The next weeks may well determine if he’s right.

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