Bernie Sanders advocated turning post offices into banks in an interview with Fusion published Oct. 20, 2015. REUTERS

While on the campaign trail, Bernie Sanders has touted a number of ways the United States can expand universal services, including for the U.S. Postal Service, which is suffering from budgetary challenges. In an interview with Fusion published Tuesday, the Vermont senator said he would turn U.S. post offices into banks.

The Democratic presidential candidate told Fusion he thinks postal banking is a "great idea" for reinvigorating the service. He said:

If you are a low-income person, it is, depending upon where you live, very difficult to find normal banking. Banks don’t want you. And what people are forced to do is go to payday lenders who charge outrageously high interest rates. You go to check-cashing places, which rip you off. And, yes, I think that the postal service, in fact, can play an important role in providing modest types of banking service to folks who need it."

This is not the first time Sanders has suggested postal banking. He wrote a 2014 Wall Street Journal op-ed advocating adding financial services and claiming the postal service's financial issues stem from Bush-era legislation. Sanders argued the financial losses at the postal service are the result of a bill in 2006 that required the postal service to pre-fund 75 years of future-retiree health benefits over a 10-year period. The financial losses are encouraged by wealthy interest groups that want to make a profit from the same services the postal service provides, he claims.

"The mandate allows the anti-government crowd to proclaim that the postal service 'is going bankrupt,' " Sanders wrote. "Their solution is to slash hundreds of thousands of jobs, close thousands of post offices, eliminate hundreds of mail processing plants, end Saturday mail, and substantially slow down mail delivery."

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Sanders offered a number of other ways the postal service could expand its offerings to generate revenue.

"The postal service should have the flexibility to provide new consumer products and services -- a flexibility that was banned by Congress in 2006," he wrote. "It is now against the law for workers in post offices to notarize or make copies of documents, to cash checks, to deliver wine or beer or to engage in e-commerce activities [like scanning physical mail into a PDF and sending it through email, selling nonpostal products on the Internet or offering a noncommercial version of Gmail]."

He cites a postal service inspector general report estimating such services could provide $9 billion a year. "It is time for Congress to save the postal service, not dismantle it," he wrote in 2014.