The government approved only 14% of eligible low-income seniors for financial assistance under the Medicare prescription drug benefit, a sign that fewer seniors than expected are applying for the benefit.

The Social Security Administration has approved only 661,000 of an estimated 4.6 million low-income seniors. This group could receive extra help worth $4,000 a year. It includes individual seniors making less than $14,355 a year and married couples with incomes below $19,245. There is no deadline to apply for financial assistance.

Dual eligibles, or those receiving both Medicaid and Medicare, will be automatically enrolled in the benefit. They make up the bulk of nursing home residents.