Navajos who want a say in changing the language requirements for anyone seeking the tribe's top two posts have until the close of business Monday to register to vote.
The tribe is holding a referendum election on July 21.
Voters will be asked if they want to determine whether candidates for president and vice president speak and understand Navajo and English well enough to hold office. They currently are required to speak fluent Navajo.
The deadline to register to vote in the November election is Oct. 9 in Arizona and New Mexico, and fast approaching in other states. For months, dozens of organizations across the Southwest have sent out armies of canvassers to register new voters.