Republican Senate candidate and Indiana Rep. Todd Rokita is facing criticism for having received money from a casino interest group that would benefit from legislation he is pushing.

The Associated Press reported that Rokita, who is running to challenge Democratic incumbent Sen. Joe Donnelly, received more than $160,000 from Native American gambling interest groups.

At the same time, Rokita has sponsored legislation called the Tribal Sovereignty Act, which would exempt tribal business from the National Labor Relations Act.

The legislation was passed as part of a larger bill that passed on Wednesday.

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According to Opensecrets.org, Rokita is also the top recipient of tribal gambling campaign donations.

The AP analysis found that while Rokita’s district does not include any recognized Native American tribes and he did not receive many contributions before the legislation, he has since received $163,250 from two dozen tribes and tribal gambling groups.

Among that cash, $8,100 came from a Michigan tribe that has a presence in Northern Indiana.

But Rokita’s chief of staff Mark Cruz, who is a member of the Klamath Tribes, defended the legislation.

“Native Americans in Indiana and elsewhere, support Todd because they know he fights for them including taking on union bosses hell-bent on exploiting poor Native American workers who historically haven’t had a voice before Congress,” Cruz said.