Coombs

[Jack Waugh]

If say an evil cabal of money-supported parties wanted to set up a spoiler effect so that minor parties wouldn't have a chance of becoming major parties, how would this cabal proceed if the voting system were Coombs? Or would the spoiler effect just happen naturally with this system, without the money parties having to do anything other than advertise? Does Coombs lead the voters to reason that if they don't give top support to a money candidate, their vote will be wasted?

[Marylander]

@Jack-Waugh It would depend on how incomplete rankings were dealt with, but the major parties would probably try to run many candidates to make it more difficult to eliminate them, and try to coordinate the bottom of their supporters' ballots to try to control the order in which their opponents are eliminated. Major parties would still have the advantage of just having more resources to communicate strategies to their supporters. On the other hand, they would face a disadvantage of being more prominent targets for opponents to try to eliminate early, and if these opponents are coordinated, even running many candidates won't help. However, if the major parties agree to coordinate with each other to keep minor parties from being competitive (or even just specific minor parties), they could make it very difficult for those parties.

Major parties could also use the fear that they will be eliminated first if they do not reach a majority to discourage defections to minor parties.