Two candidates for Standing Rock Sioux Reservation tribal chair came within one vote in Friday's recount, setting the stage for a possible contested election.

In the recount following the primary election last week, tribal chairman Ron His Horse is Thunder maintained a one-vote lead over current vice chairwoman Avis Little Eagle to advance to the September general election.

Little Eagle has until noon Wednesday to file notice that she contests the election results, but said she remains undecided whether she'll do so.

"I haven't decided anything," Little Eagle said Monday.

Either His Horse is Thunder or Little Eagle would run against former tribal chairman Charles Murphy, who had a strong lead in the primary with 565 official votes. Murphy is currently serving on the tribal council.

The official recount puts His Horse is Thunder with 220 (compared to 223 in the first tally) and Little Eagle with 219 (compared to 221).

Dellis Agard, manager of the tribe's election office, said she's prepared for a contest, and the tribe's election commission would have three days to respond to Little Eagle's notice.

The commission can certify the recount results, which would stand and be open to a court challenge. Or, it can call for another recount, or a runoff election, Agard said.

"The commission will decide what's within the law," Agard said.

The commission plans to schedule a runoff in the Running Antelope District, to resolve a tie vote between Dana Fast Horse and Adrian Kills Crow. The winner will run against Frank Jamerson, who leads in the primary election to advance to the general election.

Agard said if the commission decides for a runoff in the His Horse is Thunder and Little Eagle race, it could be held at the same time that Running Antelope District voters are already going to the polls.

She said ballots on Standing Rock are still hand counted, not optically scanned.