I wonder how the primaries would turn out if they used IRV instead of first past the post. In FPP, the candidate with the most votes wins, even if that is only 10% of the vote. For example, in NH, no candidate got over 40% of the vote, so the "winner" was not the first choice of 60% of the voters.
In IRV, you rank your first choice with a 1, and then you have the options to rank another candidate 2, and so forth until you rank them all, or only the ones you care to rank. So if I were voting Republican, I could vote:
1) Ron Paul
2) Rudy Giuliani
3) John McCain
4) Fred Thompson
and then refuse to vote for the others. What happens is that if no candidate gets 50% plus 1 of the 1st place votes, then the candidate with the least votes is eliminated. His/her voters are then shifted to their 2nd choice, if they placed one. These votes are then tallied to see if someone got a majority. If not, the next lowest candidate is eliminated and his/her votes allocated to their next choice candidate. This is done until one candidate has a majority.
There are many advantages for the voter, and with computers, this tabulation can be done in seconds. For the party, it means that the ultimate winner was at least palatable to the majority of the party, even if he/she wasn't the first choice.
The big danger with the current system is that the "winner" is completely unacceptable to a majority of the voters.
For example, let's say we were voting for dinner, and our choices are:
1) Liver
2) Salmon
3) Hot Dogs
4) Enchiladas
5) Ham
and the results are:
1) Liver 22%
2) Salmon 21%
3) Hot dogs 18%
4) Enchiladas 19%
5) Ham 21%
Liver is the winner! Unfortunately, 70% of the voters hate liver and refuse to eat. Also, 45% of the voters won't eat fish, so they split their votes between the nonfish, nonliver items, but now are forced to eat liver.
For a party, this could be a disaster. Your "winner" is unacceptable to a large portion of your party. In the fall, you have to face an opposing party without a dissatisfied base. If you had done IRV, one of the last 3 would have been the choice, and even though it wasn't the favorite, at least it's acceptable to most people.
Just a thought on how these primaries, where winners are not getting nearly 2/3 of the votes, might be improved to help parties better represent themselves in general elections.
Instant Run Off Voting