Aspen voters may decide in November if they want to do away with runoff elections in mayoral and City Council elections.

The system voters would be asked to adopt is called ranked choice, or instant runoff voting. The system allows voters to rank candidates in order of preference.

The Aspen City Council directed City Clerk Kathryn Koch at Tuesday's work session to further investigate ranked voting and decide how to best mold the system to Aspen's needs. The council would have to approve the ballot measure language before Sept. 11. Mayor Helen Klanderud said she supported letting voters decide the issue this November.

Here's how it works: Take the example of three candidates running for the same seat. If no one candidate gets 50 percent of the vote, the candidate with the least percentage of votes will be dropped from the race, and the people who voted for the third candidate would have their second vote applied to the two remaining candidates, giving one of them a majority. If there were more than three candidates, the system would repeat itself until one person got a majority of the vote.

For Aspen City Council races, where there are typically as many as eight candidates running for two open seats, the system described above would basically be used for each vacant seat. Once the first candidate is chosen, the system would repeat itself with the first-place candidate taken out of the equation.

The system also can be worked so the threshold to be elected is 33 percent, not 50.

The council appeared split on the merits of the system. Councilwoman Rachel Richards questioned a system where only people who voted for the most unpopular candidate would get a second vote. She also said the system could be confusing.

She also said runoff elections are part of democracy because they give voters another month to get to know the candidates.

Rob Richie, executive director of Fair Vote, a national group that advocates for instant runoff voting, said the system is good for democracy. Voter turnout typically takes a sharp dive in runoffs, Richie said. Instant runoff voting is also good because it eliminates spoiler candidates, Richie said.

Take the example of Florida in 2000, Richie said. Under instant runoff voting, all the people who voted for Nader would have had their votes go to their second choice, presumably Al Gore, giving him more than enough votes to carry the state.

The system has been adopted successfully for municipal races in San Francisco, Richie said.

The system also saves the city time and money. Koch said she is all for it.

Councilman Jack Johnson said the system encourages dark horse candidates, which he sees as valuable. With ranked-choice voting, people would be more likely to vote for outside candidates, knowing they could use their other choices on more mainstream candidates. Enough people voting this way may just put the dark horse over the top, Johnson said.