WASHINGTON — House Speaker Paul Ryan assured nervous Republican senators on a conference call Thursday night that he would send their “skinny repeal” of Obamacare to a conference instead of passing it into law.

As a vote neared Thursday night or early Friday morning on a proposed “skinny repeal” of Obamacare, three key Republican senators said they would only vote for it if they are assured it won’t actually become law.

The three — Sen. Lindsey Graham, R-S.C., John McCain, R-Ariz., and Ron Johnson, R-Wis.— said they needed Ryan’s word that he would not take up their legislation, pass it and send it to the president’s desk. They instead want the bill to be fixed in a House-Senate conference.

Ryan later released an ambiguous statement saying he was “willing” to go to conference if that’s the only way to move forward. “The reality, however, is that repealing and replacing Obamacare still ultimately requires the Senate to produce 51 votes for an actual plan,” Ryan said. He added that the House would expect the Senate to vote first on whatever the conference committee produces.

At around 9:30 p.m. Thursday, Graham, Johnson and a few other senators held a conference call with Ryan during which he personally assured them that he would send the bill to a House-Senate conference instead of immediately passing it. It is unclear, however, if Ryan also promised he would not pass the legislation later down the road, if that conference does not produce legislation.

“I just wanted to hear it right from Paul, we all [did],” Johnson told reporters. Those in the room are now on board with the legislation, he said.

While McCain was not in the room, he spoke to the Speaker separately, according to Johnson. He did not answer reporters questions about where he stood late Thursday.

Senate Majority Leader Mitch McConnell, R-Ky., is expected to kick off a late-night “vote-a-rama,” which would roll back a handful of key provisions of Obamacare but leave other portions of it intact, ahead of a vote on the skinny repeal bill. McConnell released the text of the skinny bill late Thursday night.

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Just hours earlier, several Republican senators admitted that the current version of the bill would drive up premiums and does not improve the healthcare system, but they argued it is a first step of a process that will later produce a better bill.

“The skinny bill as policy is a disaster. The skinny bill as a replacement for Obamacare is a fraud,” Graham told reporters Thursday.

He said it would be “the dumbest thing in history” for Republicans to pass it into law and then own the price increases in Obamacare insurance exchanges from then on.

Republican senators are considering passing a stripped-down, partial repeal of Obamacare’s individual and employer mandates that many of them acknowledge would cause premiums in the individual markets to spike. The Senate leadership is pitching this move as simply the next step in a longer process that would result in a better health care system.

Senators want to make sure the House won’t simply take up that skinny repeal and send it directly to the president, avoiding what’s sure to be a contentious conference committee to work out differences between the chambers’ two bills. The House passed a more comprehensive repeal-and-replace bill in May. (The request to go to a conference committee must, for technical reasons, originate in the House.)

In a conference committee, provisions would be added to make the skinny repeal a fleshed-out repeal-and-replace bill, they say. The Senate is using a special budget reconciliation process that requires only 50 votes to pass and constrains what can be included in the legislation.

Senate Republicans have said their bill is just a “vehicle,” and its myriad issues must be fixed later.

“It’s a means to an end to keep this conversation going, engage the House and get this to conference,” said Sen. Steve Daines, R-Mont., Thursday. “The ‘skinny’ bill in my opinion is almost like a motion to proceed, it’s a vehicle to keep it going forward.”

As of Thursday evening it was unclear if McConnell had the votes to pass the measure. McCain, has not said if he’s on board. Two key senators, including Sen. Shelley Moore Capito, R-W.Va., and Sen. Lisa Murkowksi, R-Alaska, said they had decided how they would vote but would not announce it yet.

—Yahoo News reporter Andrew Bahl contributed to this report.

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