Schatz, who supports the Sanders single-payer bill, insists that these ideas don’t have to be in direct competition with one another. The Democratic senator argues instead that Democrats should put forward a range of ideas, which the party should debate, rigorously vet, and then determine what will work best. What Schatz doesn’t want is for the party, or its left flank, to impose ideological litmus tests on health-care policy.

“With health care, somebody at some point decided that there was a bright line and that you had to pick sides. Well, I reject that view,” Schatz told me in an interview. “I think we should respect each other as colleagues, respect each other as progressives, enough to take all of these bills, and have hearings, and subject them to scrutiny.”

The senator argued that as a party, Democrats don’t insist there’s only one good policy option to deal with major issues like what to do about crumbling infrastructure, the threat of climate change, or how to reform the nation’s tax code—and he doesn’t want to see the party take a different approach with health care.

“Health care has gotten really weird politically,” Schatz said, referring to that kind of single-minded approach. “We’ve sort of tied ourselves in knots on this issue in a way that we don’t do ... for criminal-justice reform, or tax policy, or climate policy. If someone wants to do a carbon fee and someone else wants to do a cap on emissions or a renewable portfolio standard, we don’t start labeling each other as more or less progressive.”

Sanders has explicitly said that he doesn’t see single-payer as a litmus test, but some of his allies have taken a different line, insisting that it would be political malpractice not to endorse single payer. Incremental proposals to expand coverage introduced by other Democrats may face criticism from the party’s progressive wing, even if not from Sanders, as a result.

One thing working in Schatz’s favor is that Sanders himself has signed on to support the public option legislation, another signal that the Vermont senator believes there’s room for Democrats to consider a variety of health-care reforms. Sanders has previously said that he believes a public option should be available in every state as a short-term measure on health care, while he sees single payer as a long-term health-care policy solution.

“I like Bernie’s plan too, and Bernie likes my plan, so why don’t we just go ahead and have a hearing and figure this all out,” Schatz said.

Schatz’s legislation has 18 co-sponsors, all Democrats except for Sanders, who remains an Independent. A number of high-profile Democrats talked about as potential 2020 contenders have signed on in support, including Cory Booker, Kamala Harris, Kirsten Gillibrand, Elizabeth Warren, and Chris Murphy. Booker, Harris, Warren, and Gillibrand are also co-sponsors of Sanders’s single-payer bill.