CROW AGENCY, Mont. — The young woman quickly set down the decorations she was mounting on her parade float.

“That’s Tester?” she exclaimed.

She pulled out her phone and ran over to get a picture with the two-term Democratic senator who was greeting parade participants at the 100th annual Crow Fair here last month.

But it wasn’t just Tester who showed up at the multiday festival on the Crow Reservation that’s known as the teepee capital of the world. Over the course of two days, the state’s Democratic and Republican candidates for Senate and House all stopped here. It’s one of those events Montana politicians just don’t miss.

Native Americans make up about 7 percent of the voting-age population in Montana, and have been a crucial constituency for Tester, who’s won his two previous Senate elections with less than 50 percent of the vote. He’s in another competitive race this year in a state that overwhelmingly backed President Donald Trump in 2016.