Creating a public option that all Americans could choose would save $68 billion through 2020, according to a new analysis by the Congressional Budget Office.

The analysis was included in a letter to Rep. Pete Stark (D-Calif.), who along with Reps. Lynn Woolsey (D-Calif.) and Jan Schakowsky (D-Ill.) is introducing a bill this week creating a public option in the state exchanges that start in 2014.

The new CBO report scores lower savings than the public options discussed during the healthcare reform debate because they were tied to legislation that differs from the law that was enacted in March.

The bill has more than 100 Democratic co-sponsors but faces strong opposition from the insurance industry, and physicians and hospitals worried that it would bring down payment rates.