The new federal program is modeled after a Washington plan that started in 1987 but suspended in 2014 with the start of provisions of federal health care reform.

Cantwell and U.S. Rep. Jim McDermott were in Washington on Monday advocating for the state to adopt the affordable insurance program again. Cantwell said it could help about 162,000 people in Washington, who earn between $16,242 and $23,540 annually, which is just above the Medicaid eligibility rate.

The new health insurance option allows states to use money from the federal government to negotiate directly with insurance companies on behalf of low-income residents. People who would qualify have said they don't earn enough to afford the premiums for regular health insurance.

Cantwell said she advocated to have the Basic Health Plan as part of the Affordable Care Act because she saw how well it worked in Washington to have the state negotiate for group health insurance on behalf of thousands of low-income people.

"You're giving leverage for this population," she said. "We thought it was a great idea."

So far, only New York and Minnesota have adopted the new program, which Washington could add to its existing health care exchange, where people sign up for other insurance plans and the state's Medicaid option.

New York has already signed up about 400,000 people to its new basic plan, who pay about $20 in premiums per month, plus a $15 co-pay for a primary care doctor visit. Minnesota has signed up nearly 121,000 people, who pay about $16 in premiums per month.