They said Frank has also called on President Barack Obama to weigh in on the matter, answering the many calls for Pollard's immediate release, the Jerusalem Post reported Wednesday.
Pollard, a former civilian intelligence analyst, was sentenced to life in prison in 1987.
He temporarily left a North Carolina prison Tuesday to undergo an urgent surgical procedure.
Supporters said the 56-year-old Pollard suffers from a myriad of health problems, including high blood pressure.
Sources close to Pollard told the Post his health has been deteriorating for some time and he is in pain.
Pollard's wife, Esther, visited her husband last week and remained in North Carolina for his surgery.
Details about the surgery were not released in keeping with prison rules.