Updated

When Nevada voters go to the polls in this key battleground state, their choices for president will include more than the familiar names. The last entry reads "None of These Candidates" -- a unique option here that has so far survived a legal challenge by Republicans and remains popular among voters.

"The public loves having the option to express that they want to cast their ballot in favor of none of these candidates and simply send a message that all the politicians on the ballot need to clean up their act," Nevada Secretary of State Ross Miller said.

Nevada introduced the protest vote in 1975 as a way to combat voter apathy in the wake of the Watergate scandal. Some experts say it may have affected elections like that of Senate Majority Leader Harry Reid. In 1998, he beat his Republican challenger by 400 votes, but "None of These Candidates" garnered 8,000 votes.

David Damore, a political science professor at the University of Nevada, Las Vegas, also cites the 1992 presidential contest.

"When you had Ross Perot on the ballot, he did quite well here," Damore said. "The difference between 'None of The Above' was bigger than it was between George Bush and Bill Clinton in that race."

Fearing "None" could take votes away from Mitt Romney and other GOP candidates in a tight race, the Republican National Committee filed suit, arguing that because "None" is really nothing, having the option takes votes away from candidates and disenfranchises voters.

While a district court judge agreed, a federal appeals court ruled that since "None" doesn't count in the final tallies that determines winners, it would stay on the ballot -- at least for now.

While it can never win, even if it gets the most votes, "None of These Candidates" could prove to be a spoiler in a race where President Obama has seen his lead over Mitt Romney drop by more than half over the past two weeks.