I recently wrote a post for 3streams on ten types on RCV. What sorts of campaigns might they engender?
The working assumption here is that two sides will emerge in politics. They may not track party lines, but they should be identifiable if one looks at the right data in a context where the system is ‘settled.’
To summarize the 3streams post, these systems can be used to try to get any of three things: single majority winners, majority-slate sweeps, or both sides represented in a multi-seat district. It is a bit more complicated than that, but this serves to introduce the ideas that follow.
“Anybody but X” campaigning and/or electioneering. Look for this in STV and maybe AV/IRV when they are working ‘well.’ Laver (2000) pointed to this logic in a chapter on government formation.
Slate formation. Look for this in any of the multi-seat systems. Savvy candidates would want to benefit from their “vote pooling” properties. Maja Harris has been following this in Portland (OR).
Spread-the-preferences (STP) strategies. This term is from the comparative literature. It means optimizing two imperatives: run a number of candidates that can win, and ensure a more-or-less even distribution of their first-choice votes. Neighborhoods are therefore good for recruiting candidates, doing GOTV, and possibly targeting policy benefits. Watch for STP in STV and bottom-up. I need to think more about BPV. I don’t see it as a factor with numbered-post.
Fragmentation in primaries. I need to think more about this. One, running for a nomination often is not the same as running to win power. Two, that is what our best source on the history reports. Three, most papers on “exhaustion” (IIRC) point to non-majority winners emerging from fragmented fields. Four, the game theory I have seen suggests that candidates appealing to the same group of voters may not have an incentive to encourage ranking (among other issues).
Nonpartisan primaries (so-called). I have no clear prediction beyond “anybody but X.” And yet there is the game theory I just mentioned.
I may update this later. Thanks to HB for the suggestion.