Approval, Score, and Score Runoff Voting all fail the “Later No Harm” criterion, meaning giving an honest score to a less-preferred candidate could cause your favorite to lose. In elections with three strong candidates, many voters will score or approve only their favorite rather than cause their favorite to lose. If voters try to help their favorite win, Score and Approval methods will not only not elect a Condorcet winner, Approval and Score might do what plurality voting does and elect the least representative candidate, the Condorcet Loser—the one who would lose to both other candidate in a head-to-head. This is the worst possible outcome.

Instant Runoff Voting and other runoff methods (including Score Runoff), will never elect the Condorcet Loser.

None of the three methods the Theorists like have been used in a public election, so we don’t really know how voters and candidates would respond. But Approval Voting has been used in professional organizations and student body elections, so we know that in those settings most voters vote for just one candidate. Using the data from Burlington’s elections and some estimates about how campaigns and voters would use the three theoretical methods, here’s which candidate they might have elected in Burlington.

Approval Voting—most likely Republican Wright, possibly Progressive Kiss

In Approval Voting you can vote for every candidate you approve of. If Burlington voters gave an approval vote to every candidate they gave a rank to in the IRV election, Democrat Montroll would have won by a landslide 6,589 votes, Kiss would have trailed with 5,694 and Wright in last place amongst the top three candidates with 5,380.

But both the Republican and Progressive campaigns in Burlington would presumably have recognized this obvious threat from the center candidate and alerted their voters that, if they wanted their favorite to win, they should not approve the Democrat. If all voters had only approved their favorite of the top three contenders (they could also have safely approved of the Independent and Green candidates), Republican Wright would have won handily, 2,945 to Kiss’s 2585 and Montroll’s 2,045. Republican Wright was the Condorcet Loser—the candidate who would have lost to every other candidate in a head-to-head. So to the extent theorists believe that electing a non-Condorcet Winner like Kiss is a fail, electing Condorcet Loser Wright should be a catastrophe.

In student body and professional organizations that have used Approval Voting, often 80 to 100 percent of voters “bullet vote”—only approve of one candidate. If that pattern held in Burlington, Wright would have won. Even if Burlington voters were more generous with their approvals and only 70 percent bullet voted, Wright would still have won.

If Republican and Progressive voters voted only for their favorite, but all Montroll voters approved both him and their second choice, then Progressive Kiss would have won.

Score Voting—most likely Republican Wright

In Score Voting you can give each candidate a score, for example between one and nine. In Burlington, there were five candidates in the race and some voters ranked all five. If voters had given their first-ranked candidate a 9, their second choice a 6, third a 4, fourth a 2, and fifth a 1, Democrat Montroll would have won with a score of 41,020 to Kiss’s 37,515 and Wright’s 37,504.

But as in Approval Voting, the campaigns would have likely have recognized this threat (again, it’s rather obvious) and encouraged their voters to give low or no scores to all but their favorite. In fact, nearly 40 percent of Republican voters did not give either of the other two candidates a rank, so telling Republican voters not to score the other candidates would have been an easy sell. Even if some voters gave scores to all candidates so the average scores were just lower—say an average of 9, 4, 3, 2, 1—Republican Wright would have won.

Score Runoff Voting—likely Progressive Kiss, possibly Democrat Montroll

In Score Runoff Voting, as in Score Voting, you can give each candidate a score. But then the two candidates with the top total scores advance to an automatic runoff. Score Runoff advocates prefer a scale of zero to five, so let’s say that voters’ honest scores were to translate their actual rankings for all five candidates into a 5 for their favorite, 4 for their second, 3 for third, 2 for fourth, and 1 for fifth. Democrat Montroll and Progressive Kiss would have gone to the instant runoff where Montroll would have won.

Again, the campaigns would have understood the threat and likely let voters know they should give their favorite a 5 and their back-up a 1. This would minimize the chance their back-up would bump their favorite out of the runoff, but still give themselves a vote in the instant runoff in case their favorite didn’t make it. If everyone voted this way, Progressive Kiss would have won. Just like in IRV. Even if about half the voters didn’t get the strategy—say, that, within the top three contenders, voters averaged a 5 for their favorite, a 1.5 to their second-choice and 0.6 to their third—Kiss would have won.

Or say Republican and Democratic voters gave their second-choice an average of 2, but the Democrat didn’t spread the strategy since he was polling in third place, so his voters gave an average score of 3 to their second choice. Kiss would have won—the same as IRV.

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Or say polling showed voters that the Democrat would clearly beat the other candidates in a head-to-head. Republican and Progressive voters would realize their best bet was to keep the Democrat out of the runoff. They could strategically give the Democrat a low score and give their opposition candidate a high score, in hopes of sending the weaker opponent to the runoff where their favorite could defeat him. If even one-third of voters pursued this strategy, Wright and Kiss would have gone to the runoff and Kiss would have won.