Applicants to a volunteer fellowship on Sen. Elizabeth Warren's (D., Mass) presidential campaign have called the program a "great scam," claiming that operation exploits unpaid members of Warren's team.

In a report from the Daily Beast, two young men who had applied to volunteer for Warren's campaign complained that the Senator's image of a trust-busting champion of worker's rights against exploitative corporations does not match the way her own campaign is run. The applicants told the Daily Beast that they were pushed to take unpaid positions over paid ones, that they were deceived about the possibility of financial assistance and that they were asked to sign irregular nondisclosure agreements.

"What was sold to me was very different than it actually was," said Jonathan Nendze, a rising senior at Seton Hall University. "It was kind of a great scam of getting people to show up and work in the capacity of volunteer, but to function as a paid intern in the amount of work they're doing."

Concerns like Nendze's are rising as Warren continues to place worker's rights at the center of her campaign. These concerns are highlighted by the fact that Warren's campaign offers unpaid fellowships, which many other campaigns do not do. Several worker's rights groups have expressed concerns that such programs might allow campaigns to exploit unpaid labor under the guise of encouraging commitment to a cause.

Nendze said his experience volunteering for Warren confirmed those fears.

"The way they always communicated it was always fellow/intern, like they were synonymous," he said. "Their application kind of took advantage of people who were really eager to get experience."

Nendze added that when he asked about payment, campaign supervisors became evasive and unclear.

"I was getting super-concerned," he said. "I had no information about where to go, if I was being paid. If they had told me upfront that I was unpaid, maybe I would have been able to prepare better."

When asked to sign an NDA that would not allow him to "communicate with any member of the press" or "make any statement that may impair or otherwise adversely affect the goodwill or reputation" of Warren, Nendze refused.

Other applicants had similar experiences, with one applicant saying that he would receive free housing, even though he wouldn't be paid. But when he pressed campaign officials for more information, they became reticent about his options.

"Before you start a campaign you should have these basic processes done," he told the Daily Beast. "To be treated the way I was is disheartening."