Republican Sen. Steve Daines of Montana. AP

In a twist that exemplifies just how wild the healthcare debate has been, on Thursday the Senate voted on a single-payer healthcare plan. Introduced by a Republican. Who doesn't support it.

The plan, proposed as an amendment to the House bill by Sen. Steve Daines of Montana, was called the Expanded & Improved Medicare For All Act.

It was overwhelmingly voted down, with the 57 voting "no" and many Democrats choosing to vote "present." There wasn't a single "yes" vote.

The amendment was the third healthcare plan to face a key vote during the 20-hour Senate debate period. Votes on both a plan to repeal and replace the Affordable Care Act and a plan to repeal the ACA without a finalized replacement have also been unsuccessful.

The amendment would have set up a virtual universal healthcare system in which all Americans would be covered through Medicare, the federal government's health program that today covers only those who are at least 65 years old.

The intent was to try to expose which senators would vote in favor of a single-payer system.

"I do not support a single-payer system, but I believe Americans deserve to see us debate different ideas, which is why I am bringing forward this amendment," Daines said in a statement emailed to Business Insider ahead of the vote. "It's time for every Senator to go on the record on whether or not they support a single-payer healthcare system."

A representative for Sen. Bernie Sanders — who has been a proponent of "Medicare for All" — called the Republican plan a "sham" and said the Democratic caucus wouldn't be considering amendments until the final bill is out. Democrats also won't be introducing amendments until the debate period is over.

He said in a statement:

"The process Republicans have used to try to take health insurance away from millions is a sham. The Democratic caucus will not consider amendments until we see Republicans' final legislation and know what bill we are amending. Once Republicans show us their final bill, Sen. Sanders looks forward to getting a vote on his amendment that makes clear the Senate believes the United States must join every major country and guarantee healthcare as a right, not a privilege."

During the debate on Thursday, Sanders called the amendment an "old political trick."

"I hope that this is really a breakthrough," Sanders said of the bill.

"I think this is not a time for political games," he added.