James Nord, Associated Press
Democratic U.S. Senate candidate Rick Weiland, left, signs a sign at a rally in Mission, S.D., on the Rosebud Indian Reservation Saturday, Nov. 1, 2014.

MISSION, S.D. — Democratic U.S. Senate candidate Rick Weiland says his chance of beating Republican opponent Mike Rounds rests with the same voters who have carried past Democrats to victory in South Dakota: Native Americans.

Weiland and Democratic candidate for governor Susan Wismer campaigned Saturday at stops on the Rosebud and Pine Ridge Indian reservations in southern South Dakota. Voters on Indian reservations have reliably supported Democrats, but fickle voter turnout during some elections has blunted that impact. In breakout years such as 2002, overwhelming support in Shannon County, partial home to Pine Ridge, tipped Democratic Sen. Tim Johnson above now-Sen. John Thune and earned him another term. Johnson's margin of victory statewide was only 524 votes.

With Johnson retiring, Weiland and Rounds are competing with independents Larry Pressler and Gordon Howie for the open seat. The race unexpectedly turned competitive but has drifted back into the favor of Rounds, a former governor. A Sioux Falls Argus Leader/KELO-TV poll released on Monday showed Rounds 9 points ahead of Weiland.

Wismer faces Republican Gov. Dennis Daugaard in a race that favors the Republican even more heavily.

Weiland and Wismer hope for the same support and turnout that Johnson inspired 12 years ago, and Weiland told the crowd at Sinte Gleska University in Mission that 80 percent turnout among Native Americans across the state would carry him to victory on Tuesday.

"We're a few days out, and you know what? I believe the secret of this election and whether we win or lose is going to be the votes that come out of Indian Country," Weiland told the crowd of about 100. "That's why Susan and I are here."

Todd County, the home of Rosebud, where Weiland and Wismer campaigned on Saturday, has 4,877 active voters, according to the secretary of state's office. Of those, registered Democrats outnumber Republicans nearly 5 to 1. Independents nearly rival the number of Republicans.

Butch Artichoker, 74, who lives just outside of Mission, was most concerned about the Keystone XL pipeline, which would cut through South Dakota in transporting oil from the Canadian tar sands to Nebraska. Native Americans have raised strenuous objections to the pipeline because they say it could leak into the Ogallala Aquifer. Weiland has repeatedly denounced the pipeline on the stump and in debates, while Rounds has supported it, saying it would create jobs and alleviate rail congestion.

Amy Whiting shared Artichoker's concerns about the pipeline. The 62-year-old who has lived in Mission most of her life and who is raising two granddaughters said she also supports Weiland because he wants to improve education.

"I'm hoping Democrats do help us," she said, referring to the poverty at Rosebud. "I never see Republicans come on the reservation."

Artichoker said he's concerned that Pressler, who was endorsed by the Native Sun News, a weekly newspaper, could be siphoning votes away from Weiland. The Democrat didn't agree.

"No one else has bothered to show up," Weiland said. "I think we worked Indian Country hard. They know me well."