Arizona Democratic Party Campaigning for Libertarians

This is interesting.

I got a mailer from the Arizona Democratic Party urging me to vote for the Libertarian for congress. Apparently they think that they can get more bang for their campaign buck by trying to persuade people to vote for the Libertarian rather than their own candidate.

Let's think about this. Let's say that the marginal benefit of getting a vote to change from Republican to Democrat is two. That's the net change in total votes that occurs when a vote for the R is reduced by 1 while the vote for the D increases by 1. The net difference is 2. The net difference using their new tactic is one. The vote for the R is reduced by 1, but the vote for the D is unchanged.

Both of these net changes have to be multiplied by the probability that the sought after change occurs. For the new tactic to make rational sense, the Arizona Democratic Party must believe that the probability of moving an R vote to an L vote is more than twice the probability of moving it from R to D. That may well be true.

It also says something about how compelling they think their argument is for their own candidate. They seem to be using this tactic in other Arizona congressional races as well.