Arizona House of Representatives

[Хahar 🤔]

Good old-fashioned SNTV. Ugly, ugly, ugly. Just as two-member constituencies are in general.

[Хahar 🤔]

So I'm reading this article about the races for the Arizona House this fall, and I was curious to learn about their method of election. There are 30 districts, and each district elects two members (top two vote-getters). However, every voter only gets to vote for one candidate.

So if a party manages to split their vote exactly right in some districts, they have the capability of electing two candidates. Making a concerted effort to split voting would be exceedingly difficult though. Alternatively, if they run just one candidate in some districts they'd be assured of winning one of the seats, but would be abandoning even making an effort on others. There are of course numerous different strategic ways besides this that a party could use to get more members.

So my question to you all is this: What is the most effective way of electing members to the State House under this system?

Looking at the 2004 and 2006 results, and comparing Senate and House results, I'm pretty sure that voters may vote for two candidates.  All members in both houses are elected every 2 years from 30 legislative districts, one senator and two house members.  So it is similar to Washington, except that senators are elected to 2 year terms, and thus there is a senate race in every LD

A second difference is that the house members are not elected by position, but rather in a single contest where a voter may cast two votes, and the top 2 candidates are elected.  If you compare the total vote in each house race to the total vote in the senate race for the same LD, the ratio is much greater than one, but remarkably less than two.  On a partisan basis, in districts where both major parties ran a senate candidate and two house candidates, the ratio is typically in the 1.6 to 1.8 range.  The vote for the two house candidates of a party are typically similar, and too close together to be the result of voters casting a single vote (unless the Republican and Democratic parties in Arizona are as disciplined as Sinn Fein in Northern Ireland).

By comparing results, it appears that there are a large share of partisans voters, but many of these do not vote for two candidates of their party.  On top of this there are some bi-partisan/independent voters.  I would suspect that some deliberately choose one candidate from each party.

In reasonably close districts, if most of the single-vote partisans vote for one of their two party's nominees, it can result in the leading candidate getting 20-30% more votes.   This may be enough for the leading candidate from the minority party to defeat the 2nd candidate for the majority party.

It appears that there may a tactical advantage for the minority party to run a single candidate.  This forces its partisans to vote for that one candidate, even if they only use one vote.  It also forces deliberate bi-partisans to vote for that single candidate.

So let's say that a district has a 50-10-40 D-I-R partisan balance.  But that is further split:

30% 2-vote Democrats.
20% 1-vote Democrats.
10% 2-vote deliberate bipartisans.
25% 2-vote Republicans.
15% 1-vote Republicans.

And let's say that that the 1-vote Democrats vote heavily for Don Key, while the bipartisans split their Democrat vote between Don Key and Betty Blue.   Meanwhile the 1-vote Republicans, and the bipartisans split their Republican vote between Ellie Funt and Rick Red.

If there are 1000 voters, the vote might be broken down among 2-vote partisans, Democrat 1-vote partisans, Republican 1-vote partisans, and 2-vote bipartisans.

Don Key:     300 + 150  +    0 + 50 = 500
Betty Blue:  300 +   50  +    0 + 50 = 400
Ellie Funt:    250 +     0  +  75 + 50 = 375
Rick Red:     250 +     0  +  75 + 50 = 375

Don Key is easily elected, but Betty Blue has only a narrow lead over Ellie Funt and Rick Red.  If Rick Red were not on the ballot, then Ellie Funt might get another 125 votes and also be elected (very few 2-vote partisans will use their 2nd vote to vote for a candidate of the other party).

Meanwhile Betty Blue has to encourage more Democrats to either vote twice, or to vote for her instead of Don Key, and also to encourage bipartisans to vote for her rather than Don Key.

In 2006, there were:

9 LDs with 2 Republican and 2 Democrat candidates:

4 DD-RR (2 Democrats elected)
3 RR-DD (2 Republicans elected)
1 RD-RD (split delegation with GOP 1st and 3rd)
1 DR-DR (split delegation with Dems 1st and 3rd)

9 LDs with 2 Republican and 1 Democrat candidates

7 RR-D (2 Republicans elected)
2 RD-R (split delegation)

6 LDs with 2 Democrat and 1 Republican candiates,

6 DD-R (2 Democrats elected)

5 LDs with 2 unopposed candidates - other than 3rd party

4 RR- (2 Republicans elected)
1 DD- (2 Democrats elected)

1 LD had one R and one D candidate, resulting in a split delegation

1 RD-

So of the 24 contested LD's, 4 elected split delegations.  Several of the others were reasonably close.  The 4 split house delegations were among the 12 LD's where the senate race was within a 60-40 margin.

For details see the 2006 senate and house results for LD 10, 11, 25, and 26.  Also LDs 5, 23, and 24.

2006 Arizona General election.

Jim, I'm certain you're a robot.