I am reproducing here a Tweet thread from last week:
I expect a two-serious-candidate equilibrium, with ballot exhaustion driven by the supply of hopeless candidates.
The basic logic comes from Cox (1997). Winning-minded elites will be thinking about the IRV round when deciding whom to back in the “final five” round.
That means we need to think about the strategic context of an IRV election, which will ‘contaminate’ the first round.
What does a winning-minded-elite do in an IRV election? They get together with other winning-minded-elites and coordinate on the person most likely to win.
It turns out that humans have routinized such coordination. The general term for this is “political party.”
It follows that ‘resources’ will not flow to hopeless candidates, leading us straight back to two-party equilibrium. Or, in lopsided districts, two-faction equilibrium.
I covered these issues in my Apr. 2021 review of The Politics Industry. That review included discussion of ‘nonpartisan IRV’ in a two-party-competitive city (Cleveland, 1913-19). TLDR: lots of ballot exhaustion, no independents elected.
People (like me) who oppose Final Five are aware of the dynamics above. Our worry, I think, is that all we’ll have done is weakened political parties even more.
…and we don’t know what the world would have looked like if all these nonpartisan elections had never been adopted. Small changes have big consequences… even if parties adapt to nonpartisan elections.