U.S. Senate candidate Dave Domina appeared at the Winnebago Tribe's powwow in July. Photo from Dave Domina

The Winnebago Tribe has endorsed Dave Domina for the open U.S. Senate seat in Nebraska.

Domina, an attorney, has met with the tribe three times this year, including the 148th annual homecoming powwow in July. The visits were "eventful and extremely influential," according to a press release.

"Thanks to Ho-Chunk Winnebago Nation for the guest invite to annual Homecoming Pow Wow. Solemn, beautiful event," Domina said on Twitter at the time.

Domina is facing Republican Ben Sasse for the seat. Polls show Sasse with a considerable lead against Domina, according to Real Clear Politics.

Native Americans make up just 1.3 percent of the state population. But they make up nearly 56 of the population in Thurston County, which is home to the Winnebago Tribe and the Omaha Tribe.

The seat is being vacated by Sen. Mike Johanns (D-Nebraska).