Gerrymandering in New Hampshire
by Phil Hatcher
In this in-depth look at redistricting in New Hampshire, Dover Democrats Co-chair Phil Hatcher explores how Republicans will gain an electoral edge unless we win the fight for a fair, rational and constitutionally-correct redistricting plan.

The decennial electoral redistricting in New Hampshire is well underway. The NH House Special Committee on Redistricting has approved maps for the Congressional districts and the NH House districts, and they will be voted on by the full House during their January 5-7 sessions. The NH Senate Election Law and Municipal Affairs Committee will begin deliberations in January for the NH Senate and Executive Council maps. All the maps must ultimately be approved by both houses of the legislature, as well as by the governor.
Republican Lawmakers’ Gerrymandering Plan
So far, the process has been highly partisan. The House special committee approved their maps on 8-7 party-line votes. The process has been a bit more transparent than in 2011-2012, in that the Republicans have made clear that partisan advantage is a key component of their decision process. There have also been listening sessions in every county where the public could provide input, and there were two public hearings immediately prior to the final votes by the special committee. However, it is clear that the public input has been largely if not entirely ignored by the Republicans.
For example, the special committee approved highly gerrymandered Congressional districts, and no one spoke in favor of these districts at the two public hearings. The Republicans’ premise for the districts was to reunite the towns of the “southern tier” with Manchester, but no one at the county listening sessions asked for this. And many people asked that fair districts, meaning ones with competitive elections, be created, which was not done. But, elections have consequences, the Republicans won in 2020, they have the power, and they plan to use it. The public be damned.
SInce the Congressional map has gotten a great deal of press and notoriety, in this piece I will focus instead on the NH House maps. The Republicans also did a terrible job here, but there are some technical and constitutional issues that make NH House maps more difficult to construct and thus harder to understand. I will try to unpack those issues as I take a look at what has been proposed for the House maps, with a special focus on the maps for Strafford County.
New Hampshire’s Redistricting Laws and Procedures

The first constitutional requirement is known as “one person, one vote.” This simply means that the number of residents for each House representative should be approximately the same. The ideal number of residents per rep is simply the total number of state residents divided by the number of reps. For the 2020 census this ideal number is 3444. Courts have ruled that the total spread in the deviation from the ideal should be no more than 10%, meaning districts should be no more than 5% below the ideal, nor more than 5% above the ideal.
Additionally, the districts must be constructed from towns and city wards. Neither a town nor a city ward can be subdivided. And, towns or wards placed into a district must be contiguous. The legislature has also placed a constraint on redistricting by requiring that districts not cross county lines. This is because, by law, county government is currently organized around the county’s delegation of House reps.
These constraints, along with the large number of reps (currently 400, with the NH constitution stating that it must be in the range of 375-400) makes it very difficult to construct districts that satisfy “one person, one vote.” Since the ideal population per rep is only 3444, a district with a single rep must have a population in the range of 3272-3616 (5% below to 5% above ideal), a fairly tight window of 345 when you consider all the constraints. Multi-rep districts can be employed to create a larger window. For instance, a two-rep district would ideally contain 6888 residents, with an acceptable range then of 6544-7232, giving a window of 688. But the NH constitution puts constraints on how towns and wards can be combined together to form larger districts.
In particular, the constitution states that towns and wards that have a population equal to or larger than the ideal population should be given their own district. But, the “one-person, one vote” principle still applies, so floterial districts are used to soak up the excess population in these single-town districts.
Base and Floterial Districts
A floterial district is a district that “floats” above other base districts, all of which must be contiguous. Consider how Dover Wards 3 and 4 are currently assigned House districts. Each district is above the 2010 ideal population, so they each get their own district with their own dedicated rep. And a floterial district exists that includes both wards, adding one more rep, shared by both wards, to properly support the “one person, one vote” principle.
But, how do we evaluate in this case whether the correct number of reps have been assigned? The NH Supreme Court has endorsed a method, known as the component method, for calculating population deviations for floterial districts. The idea is to compute a town or ward’s portion of the shared rep by examining the relative populations of the towns or wards in the floterial.
For example, let’s look at Dover Ward 3, which had a population of 5028 in 2010, when the ideal population was 3271. Dividing these two numbers gives 1.5278, meaning that Ward 3 should get that number of reps. It gets one dedicated rep since it is given its own base district. And to compute its share of the floterial rep, we divide the Ward 3 population by the total population of Wards 3 and 4. The Ward 4 population in 2010 (5134) is slightly bigger than the Ward 3 population, so Ward 3 is only awarded .4948 of the shared rep, giving Ward 3 1.4948 reps by the component method. Since 1.4948 is within 2% of the 1.5278 ideal rep assignment, this is an acceptable deviation.
The NH constitution also requires that a town or ward that has a population below the ideal population must be placed in a non-floterial district (i.e. in a base district). This, of course, requires that the town be combined with another adjacent town to form a larger district, worthy of at least one rep. This district can then be a base district for a floterial, but the small town cannot be placed in a floterial by itself.
The requirement for how to handle a town or ward with a population equal or above the ideal population conflicts with the requirement for how to handle smaller towns and wards. In some cases, it causes an eligible town or ward to not be given its own district.
Consider the town of Madbury. It is surrounded by towns and wards that all have populations above the ideal population. But Madbury’s population is below this threshold. It has to be combined with one of its neighbors, and whichever one is chosen will not be given its own district, seemingly violating the constitution, but it is unavoidable. In 2010 the map builders put Madbury with Durham, denying Durham its own district.
An eligible town or ward might also be denied its own district if it has to be placed in a base district with another town or ward in order to satisfy the math mandated by the “one person, one vote” principle. That is, sometimes the 10% deviation windows are just too tight and need to be expanded by combining towns together to form a larger base district.
Constitutional Priorities
So, creating NH House districts is hard, and it may be impossible to always fulfill all the constitutional requirements. However, I believe that these requirements should be considered as higher priorities than any non-constitutional consideration. For instance, some people dislike large floterials (although they usually do not specify what the exact dividing line is between acceptable and too large, nor do they usually even provide a metric to be used, such as total population or geographic size). But I believe that no eligible town or ward should be denied its own district simply to avoid a floterial district that someone thinks is too large.
This brings us to the proposed NH House maps for the 2020 census. The map approved by the special committee for Coos County denies Berlin its own district. The supporters of this map stated they denied Berlin because otherwise there would be a floterial that would be too large. They never provided any criteria for how to evaluate the size of a floterial and the opponents of this map rightfully accused them of hypocrisy because the approved maps for other counties included floterials that many thought were equally large.

Of course, the likely real reason that the Republicans decided to combine Berlin with Jefferson in a base district was for partisan advantage. Berlin voted for Biden by 53% to 46%, while Jefferson voted for Trump by 60% to 39%. While Jefferson is a much smaller town, using it to weaken Berlin’s lean to the Democrats increases the probability that a Republican House candidate will be elected from Berlin.
The Republicans on the special committee were quick to point out that the US Supreme Court has said that redistricting is a political exercise, and gerrymandering is not itself unconstitutional. But to ignore the NH constitution in order to gain partisan advantage should certainly be a violation of the NH constitution, and hopefully the NH courts will respond accordingly if the Coos County map is challenged on this point.
The map approved by the special committee for Strafford County denies six eligible towns or wards their own districts, despite the fact that the current (2010) map only denies four, the Democrats’ proposal for 2020 only denies three, and the nonpartisan Map-A-Thon map only denies two. Again, I feel the approved map violates the NH constitution, as there appears to be no justification for denying so many towns and wards, and tellingly the Republicans offered no justification during the committee debate.
The Republican map puts Rochester Ward 5 into a non-floterial district with Milton, and it places Dover Ward 4 into a non-floterial district with Madbury and Lee. All these towns or wards, other than Madbury, are big enough to be eligible for their own district, so this is four of the denials. The other two denials are due to placing Barrington and Strafford, both eligible for their own district, into a non-floterial district.
These Strafford County maneuvers are not quite so blatant as with Berlin in Coos County, but certainly they were designed to gain some partisan advantage. Analysis by America Votes indicates that the main change from the 2010 map is a change of 3 seats from Strong Democratic to Lean Democratic. Analysis by the Map-A-Thon project indicates that the Republican 2020 proposal would have one more Lean Republican seat and one fewer competitive seat, when compared to the Democratic 2020 proposal.
This seems like a very modest partisan gain for the Republicans in return for them blatantly ignoring the constitution. In addition, their insistence on splitting off a ward from both Rochester and Dover ignores the public testimony at the Stafford County listening session, when many people asked for city wards to not be joined to neighboring towns. Both the Democratic and the Map-A-Thon proposals keep Dover and Rochester intact while satisfying the “one person, one vote” principle and giving more eligible towns and wards their own districts.
In addition, the Republicans made the district for Dover Ward 4, Madbury and Lee a base district in a floterial that also contained the district for Durham. This floterial district has a total population of over 27,000. The floterial that the Democrats proposed for Coos County, which the Republicans said was unwieldy, has a population of only about 13,500. It is true that the Coos floterial has 17 towns, but 13 of them have a population of less than 10 (with 10 towns having a population of zero). Clearly, what is an unwieldy floterial is in the eye of the beholder!
The 2010 map for Strafford County includes a district combining Strafford and New Durham, even though those two towns only meet at a point, and do not in fact share a border. Is this considered contiguous? It is not clear. The Republican 2020 proposal avoided this in the construction of the base districts, but included a floterial that relies on Strafford and New Durham being contiguous. The Democratic 2020 proposal avoided it altogether. However, the Map-A-Thon map does use this point connection. Why? Because doing so allows a map to be found that only denies two eligible towns their own district.
The Democratic and Map-A-Thon Plans
Both the Democratic proposal and the Map-A-Thon proposal deny Durham its own rep by combining it with Madbury. The Democratic proposal denies Farmington and Milton their own districts but gives Strafford its own. The Map-A-Thon proposal denies Strafford, but gives Farmington and Milton their own districts. Therefore, the Democratic proposal denies a total of three eligible towns, and the Map-A-Thon proposal only denies two.
The Map-A-Thon project used software, which actually I wrote, that tries to automatically and exhaustively (within certain constraints) find possible NH House maps for a county. This software worked to maximize the number of eligible towns that receive their own district, while fulfilling all the other constitutional requirements. The software could be configured to either consider meeting at a point as being contiguous, or not.
Running the software on Strafford County indicated that the only way to get to no more than two denials is by connecting Strafford and New Durham through that point. And two denials is the best you can do for this county. So the Map-A-Thon project decided to continue to exploit that point connection in order to better fulfill the constitutional requirement that eligible towns get their own district, especially since the point connection had been exploited in the map adopted after the 2010 census.

The Republicans’ cavalier attitude toward awarding eligible towns with their own district is based upon a misreading of the NH constitution. To be fair, the wording used to state this requirement is not clear. The constitution states (Part 2, Article 11): When the population of any town or ward, according to the last federal census, is within a reasonable deviation from the ideal population for one or more representative seats, the town or ward shall have its own district of one or more representative seats. The Republicans insist on a literal reading of these words, meaning that to be eligible a town or ward’s population must be within 5% (plus or minus) of an even multiple of the ideal population for one rep. But the legislative record for the 2006 amendment that added these words to the constitution is very clear that the literal reading was not the intent. When Sen. Robert Flanders, a Republican, introduced it in the Senate, he said, “This [amendment] provides that when a town or ward has enough inhabitants to equal or exceed the number required for one representative seat, it shall have its own district.”
But an additional problem with the Republican maps is that they were proposed with inadequate explanation or justification. When challenged on specific points, they usually refused to discuss their reasons. So, the public has no clear idea why Dover Ward 4 was pulled out of Dover and joined with Madbury and Lee. Likewise, the rationale for connecting Rochester Ward 5 to Milton was never given. We suspect partisan advantage was the goal, but we do not really know.
Residents of a district should understand why its boundaries were drawn the way they were, even if they don’t like it. Instead we have politicians who want us to think, apparently, that redistricting is too complicated for us mere mortals to understand, and we need to accept whatever they give us.
I hope this piece helps you to see the many flaws in what the Republicans have proposed for the new NH House districts. I encourage you to advocate that their proposed maps be rejected when the full House meets during their January 5-7 sessions.
About the author:

Phil Hatcher retired from UNH in 2019 after 33 years teaching computer science. He and his wife, Peggy Kieschnick, have lived in Dover since 1986. They have two children and one grandchild, all living in Brooklyn, New York. This makes them wonder: why can’t we keep our young people in New Hampshire?