A new study finds far more Republican Senate offices pay their interns than Democrat offices do.

Nearly 51 percent of Republican Senate offices offer paid internship compared to just 31 percent of Democrat offices, according to a new study from the bipartisan group Pay Our Interns. On the House side, only 8 percent of Republican offices pay their interns compared to just 3.6 percent of Democrat offices.

"Democrats like to say, ‘Well, you know, you're getting paid with knowing that you're making a difference, Republicans have no illusions that people should get paid for their work," Carlos Mark Vera, one of the study's authors told the Washington Examiner.

From 1973 to 1993 it was standard practice to pay interns working in the House of Representatives under the Lyndon Baines Johnson Congressional Intern Program. The program provided a $1,000 two-month internship to students. However, Congress has not appropriated funds for it since the early 1990s.

Much of the reason many internships are unpaid on Capitol Hill can be attributed to hiring caps. Each representative is limited to 18 paid positions and an additional four positions on their staff.

Vera, says the lack of paid internships provided by Congress combined with high cost of living in the District of Columbia is preventing minorities from pursuing internships on Capitol Hill. He notes there is a great disparity between the participation of Caucasians in internship programs compared to Hispanics and African-Americans.

His study finds Hispanic-Americans have the lowest rate of internship participation, at 53.3 percent, compared to Caucasians at 68.2 percent. African-American participation stands at 59.5 percent, while Asian-American participation is 63.2 percent.

Vera argues unpaid internships favor those of higher socio-economic status because only those who can afford to work for free or have parents that can support their child can seek those opportunities. As a first-generation immigrant from Colombia, Vera says the goal of Pay our Interns is to make public service careers more accessible to minorities and those of all socioeconomic backgrounds, not just on racial lines.

"We're also fighting for the sons of coal miners in West Virginia, this is about opportunities for anyone to enter public service," Vera said.

Pay Our Interns collected their data by contacting members of Congress directly, often meeting directly with representatives and surveying their websites.

The report concludes that while unpaid internships often provide valuable learning experiences, a lack of adequate pay adversely affects minorities, producing a less diverse Capitol Hill workforce. It also recommends raising hiring caps and more transparency concerning how much members, if at all, pay their interns.