"If people don't like the private insurance that they're getting, they should have a Medicare-type public option available in every state in this country," Sanders said on CNN's "State of the Union."
Sanders, an independent senator who caucuses with Democrats and became a member of the Senate Democratic leadership following his presidential bid last year, has long made a call for universal coverage one of his key objectives.
Asked on Sunday if he would follow through on his pledge to submit single-payer legislation, in which the government would shoulder the health care costs for all, Sanders said, "Absolutely, of course we are."
As part of this new push for single-payer legislation, Sanders said his team was looking at a way to build a popular consensus around health care as a right, regardless of income level.
"We're figuring out how we can mount a national campaign to bring people together," he said.
Sanders conceded that it was a politically difficult proposal, not just because Republicans control the levers of power in Washington and are strongly opposed to such a large government program, but because of the entrenched interests standing against it. He pointed to those same interests when asked why an attempt to build a single-payer program in Vermont had collapsed.
"Taking on the insurance companies and the drug companies, taking on Wall Street, taking on a lot of very powerful forces that make billions of dollars a year from the current health care system is not going to be easy, and it's not going to take place until millions of people get involved in this struggle," Sanders said.
Open door to 2020
Sanders has campaigned around the country for months on health care, decrying Republican attempts to repeal Obamacare and pushing Democrats to the left on the issue.
The senator's reference to planning a national campaign on health care came as he is due to speak in Iowa next month to promote his book, the "Bernie Sanders Guide to Political Revolution," which has compounded speculation that he is planning a 2020 bid.
Sanders again declined on Sunday to say what his plans were one way or the other, although he allowed for the possibility that he would run for president again.
"We got three years before the presidential election," Sanders said. "We got plenty of time for candidates or potential candidates to make decisions."