A new report says raising the eligibility age for enrolling in Medicare won't produce nearly the cost savings that had been assumed previously.

The Congressional Budget Office analysis says that phasing in an increase in the eligibility age from 65 to 67 years old would lower the by just $19 billion over the coming decade. Savings would rise more in future years, however.

The CBO report says many people who otherwise would be on Medicare would be eligible for subsidies under the new and that many others would receive primary coverage through their employer or their spouse's employer.

Raising the retirement age is a proposal embraced by budget hawks, particularly Republicans seeking to lower the program's unsustainable growth.