Third party members and alot of people have just been seriously punked by Instant Runoff Voting. It may take them a few years to figure it out, but it will be too late then. IRV hurts third parties and solidifies two party domination.
Just look at the history of IRV in real life:
In San Francisco, elections have many, many candidates and thus majority failure in the first round is common. In no case did the vote transfers change the preference order affecting the top two candidates in the first round; i.e., the leader in the first round won the election, and the runner-up in the first round remained the runner-up. This, then, can be expected generally in IRV elections. Australian experience with IRV shows that this is what it normally does.
Here are some more observations about IRV's impact on third parties.
The Libertarian Reform Caucus writes: "Anyone for a Bullet in the Foot? Instant Runoff!" IRV can be trusted to maintain a two-party system. When lawmakers on the hill realize this, what's to stop them from building whole-hearted bipartisan suport for IRV? Some in Congress already say they like it! If nothing is said against IRV, one day we'll all be worse off than we were with Plurality Voting! IRV lovers don't know where they're pointing their pistol!...in ordinary scenarios, if a group of major party supporters conspires to rank their favorite candidate lower they can push up that candidates chances of a win! And vice-versa. Ranking lacks meaning in IRV.
Australian Politics - in Australia, they call the ranked type voting for single contests - Preferential voting.
According to the analysts at Australian Politics, the "Disadvantages of the Preferential [IRV] System" are:
- It is more complicated to administer and count.
- It can produce a higher level of informal voting.
- It promotes a two-party system to the detriment of minor parties and independents.
- Voters are forced to express a preference for candidates they may not wish to support in any way. (The use of optional preferential voting, as used in New South Wales State elections, is a solution to this problem.)
The facts are there are three IRV countries: Ireland (mandated in their 1937 constitution), Australia (adopted STV in the early 1900s, but in 1949 added "reweighting" to STV in their multi-winner elections, a change which does not matter for us since we are only considering single-winner elections - Australia and Ireland have both kinds of elections), and Malta. (Later note: a recent addition is Fiji, but it unfortunately then got subtracted due to a 2006 coup.)
All three became 2-party dominated in their IRV seats. And this is despite the fact that in addition to IRV single-winner elections, they all also have multi-winner STV "proportional representation" (PR) elections, and they are parliamentary rather than presidential. Both of these two factors mitigate toward having more than two parties (the parliamentary countries with PR essentially all have many more than two vibrant political parties). But despite those multiparty-genic factors, the effect of IRV in these countries has been enough to drag them back down to two-party domination status!
So given that, you can bet your bottom dollar that the USA, were it to adopt IRV but still to remain presidential and without multiwinner PR elections (i.e. wholy with single-winner elections), will definitely stay two-party dominated.
According to Wikipedia, the minor parties (e.g. The Australian Democrats, Greens, One Nation, Family First, Christian Democrats) are often able to hold Senate seats thanks to the multiwinner PR system used to elect it, but have usually been unable to hold House seats thanks to the fact that they are elected using IRV. As I write this in 2004-2007 the total number of House seats owned by these parties is zero out of 150. (There is a seat owned by CLP member Dave Tollner, but the County Liberal Party is really the Liberal/National party branch in the Northern Territories.)
Has IRV helped third parties anywhere?