“This single-payer, it's the gold standard for the Democrats,” Daines, who does not support single-payer himself, said in a brief interview on Thursday afternoon ahead of the vote. “In fact in the House, 115 Democrats have co-sponsored this exact bill we're going to vote on today. 115, that's about 60 percent. President Trump, the Republicans, want to make America great again. The Democrats want to make America like England again. This is a clear choice."

Support for single-payer has increased among congressional Democrats in the wake of the 2016 election. According to Daines’ office, the amendment put forward by the senator is identical to single-payer legislation sponsored by Democratic Representative John Conyers, which now has the support of a majority of House Democrats, a threshold crossed after Trump won the White House. Sanders plans to soon introduce his own “Medicare for all” legislation. But Democrats are far from united in embracing single-payer legislation, and congressional Democratic leaders have not included single payer as part of any kind of formal Democratic agenda.

Ahead of the vote on Thursday, Conyers said in a statement that his legislation was being used “as a pawn,” charging that “the process by which the Senate is considering changes to our nation’s healthcare plan is a sham,” and adding that “Senate Democrats are right not to take part in it.”

Sanders took to the Senate floor ahead of the vote to denounce Daines’ amendment. “I suspect that what Senator Daines is doing is nothing more than an old political trick, trying to embarrass Democrats,” the senator said in his remarks. "I hope Senator Daines has seen the light, but I suspect not, and I suspect it's just a political game,” he added.

The Vermont senator added he does hope soon to have a debate, in good faith, on the idea of single payer. “I do hope, by the way, at some point within this debate, if we can, if not, certainly in the near future, to, in fact, be introducing a Medicare-for-all, single-payer program,” he said. “It will be somewhat different than my friend John Conyers' bill in the House, but what it will do is say that in America, if you are rich or if you are poor, if you are a man, woman, and child, yes, you are entitled to health care as a human right and not a privilege."

A better gauge of how many Senate Democrats are willing to back a single-payer proposal will be the number that sign on to the legislation that Sanders plans to introduce.

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