What if Brazil adopted the Distritão?

[President Punxsutawney Phil]

There have been multiple proposals to reform the Brazilian Chamber of Deputies to adopt mid-sized districts under single non-transferable vote. This idea has gained some controversy. I am seeking to find out what the districts would look like if combined with apportionment methods getting rid of the current cap and minimum numbers of deputies for a state. Since the results of the 2022 Census results are not out yet, I am forced to use the 2010 Census results.

[President Punxsutawney Phil]

Sao Paulo 41,262,199 (111)
Minas Gerais 19,597,330 (53)
Rio De Janeiro 15,989,929 (43)
Bahia 14,016,906 (38)
Rio Grande do Sul 10,693,929 (29)
Parana 10,444,526 (28)
Ceara 9,883,640 (26)
Pernambuco 8,796,448 (23)
Para 7,581,051 (20)
Maranhao 6,574,789 (18)
Santa Catarina 6,248,436 (17)
Goias 6,003,788 (16)
Paraiba 3,766,528 (10)
Espirito Santo 3,514,952 (9)
Amazonas 3,483,985 (9)
Rio Grande Do Norte 3,168,027 (8)
Alagoas 3,120,494 (8)
Piaui 3,118,360 (8)
Mato Grasso 3,035,122 (8)
Distrito Federal 2,570,160 (7)
Mato Grasso Do Sul 2,449,024 (6)
Sergipe 2,068,017 (5)
Rondonia 1,562,409 (4)
Tocantins 1,383,445 (4)
Acre 733,559 (2)
Amapa 669,526 (2)
Roraima 450,479 (1)
Brazil 190,755,799
371,844 per member
513 in total

[President Punxsutawney Phil]

Japan was the first nation in the world to use this system of voting. As such, mirroring the general style of how it was used in the Japanese House of Representatives until electoral reform in the 1990s, I am likewise working with districts sized between three to five. States smaller than that in allotment will nonetheless form districts to themselves.

I wish I could modulate results in a more general way here, but Brazil has a crazy variety in parties and I doubt something like this could in any real way simulated. I will seek to mark if Lula or Bolsonaro won a given constituency in the second round of the elections, if so possible.

[President Punxsutawney Phil]

Roraima forms the only single-member district. 450,479 amounts to 1.211 quotas, which is far from enough to get a second member. Needless to say, this voted for Bolsonaro. The elimination of the cap hits Roraima hard, and it falls from 8 to one deputies.

[President Punxsutawney Phil]

Amapa's 669,526 people nets it 1.801 quotas, which rounds up to 2. This produces 334,763 per member.
This district itself is closely divided between left and right and would be likely to elect one deputy from each - a fairly safe call given what we know about how this electoral system behaves. Bolsonaro narrowly won here.

[President Punxsutawney Phil]

Acre doesn't exist...it was made up by Brazil, to claim land that was previously Bolivian, so it has no members in the Chamber of Deputies.
Acre has 733,559 people, which amounts to 1.973 and rounds up to 2 - 366,780 per member. This is Bolsonaro-land. Lula got a vote share here comparable to what Democrats get in West Virginia or Arkansas in federal elections.

[President Punxsutawney Phil]

Tocantins' 2010 population of 1,383,445 nets it 3.720 quotas, which produces four members - 345,861 per member. This district would be very likely to elect one PT deputy, or have the potential to do so. Lula won here, making this our first Lula-won  district.

[President Punxsutawney Phil]

Rondonia has 1,562,409 people, which translates into 4.202 quotas, four members, and 390,602 people per member. Bolsonaro obviously won here. Maybe one left-leaning deputy is elected here...four as a seat magnitude makes it pretty hard for the right to sweep. Two, on the other hand...

[President Punxsutawney Phil]

2,068,017 people in Sergipe is equal to 5.562 quotas, which rounds up to six. But since  all states being rounded to the closest intreger above 0 would result in 518 deputies, I needed to take one seat from five states each. These states were selected on the basis of being the closest to not having their last seat. Sergipe ultimately turned out with five, which equals 413,603 per member, likely the second-highest such ratio after Roraima. Sergipe is the biggest state to have an at-large district. Sergipe voted for Lula.

[President Punxsutawney Phil]

Mato Grasso do Sul's 2010 population was 2,449,024, which totals 6.586 quotas. It, just like Sergipe, lost a deputy from corrections in the final stage of seat allocation. Still, six needs to be divided. I had no choice but to divide it into two three-seaters. I made the choice to split it among intermediate-region lines, with allowance made for population equality. These "intermediate-regions" (regiões intermediárias) were introduced in 2017 and are logical building blocks for districts of this sort. They are further divided into what I will call "immediate regions" (Região Geográfica Imediata). The state itself has 408,171 people per member.

The second district takes in the intermediate regions of Dourados and Corumbá, and the immediate region of Coxim within the intermediate region of Campo Grande. Together these should be just a bit, slightly more populous than the rest of the state, which forms the first district. Both of these should be Bolsanaro-won. The one to the west is the 2nd district, the one to the east is the 1st (I try to assign the first district to whichever district has the state capital).

[President Punxsutawney Phil]

7/29 states done. Thus far, anyway. But these states together only have 24/513 seats in the Chamber of Deputies. They have perhaps 15 percent of the Brazilian land area and roughly as much population as the US state of Virginia.

[President Punxsutawney Phil]

Distrito Federal has 2,570,160 people, thus it has 6.912 quotas. This rounds up to seven. (There are some states along the way that will round down. Stay tuned.) Seven members means 367,166 people per member. This makes two districts, one electing three and one electing four, inevitable. I tried to draw a doughnut arrangement but the population distribution didn't work. So I instead drew it east-west.

The first district is composed of the municipal districts of Gama, Recanto das Emas, Riacho Fundo, Samambaia, Taguatinga, Ceilandia, Guara, and Brazlandia. Its 2010 population was 1,493,896 and it elects four deputies - 373,474 per person.

The second district is composed of the municipal districts of Brasilia, Cruzeiro, Guara, Candangolandia, Nucleo Bandeirante, Lago Sul, Santa Maria, Lago Norte, Sobradinho, Sao Sebastiao, Paranoa, and Planaltina. Its 2010 population was 1,076,254 and it elects three deputies - 358,751 per person.

Both these districts at least likely voted for Bolsonaro, but they would both elect likely at least one centrist and/or left-leaning deputy.

[President Punxsutawney Phil]

3,035,122 people reside in Mato Grasso. This yields 8.162 quotas, and eight members. There are 379,390 people per member.

Under eight members, you can have two four-seaters or a three-seater and a five-seater. In the end, I opted for the former. Mato Grosso has five "intermediate regions", and they were the basis for how I drew Mato Grosso into two districts of roughly equal populations.

The first district is composed of the intermediate regions of Cuiaba and Caceres. The second district is composed of Barra do Garcas, Rondonopolis and Sinop. Both voted for Bolsonaro and would be practically certain to elect more right-leaning than left-leaning deputies, from their four in total.

[President Punxsutawney Phil]

Piaui has 3,118,160 people, and from that it has 8.386 quotas. This yields eight members and 389,770 people per member.

I decided to draw a three-seater constituency centered on the state capital and a five-seater covering the rest of the state. The first district is formed from the immediate regions of Teresina and Barras within the intermediate region of Teresina, and the second district is the rest of Piaui. The former is probably more right-friendly than the latter, but Lula probably still won here anyway. The second district in particular would have a massive left lean and I could easily see PT winning two seats here.

This brings our current count of Lula-Bolsonaro seat voting to 10 Bolsonaro-4 Lula. This Bolsonaro lead is the result of Bolsonaro doing somewhat better among smaller states than Lula did.

[President Punxsutawney Phil]

Alagoas' 2010 population is 3,120,494, which gives it 8.392 quotas. This rounds down to eight members. This in turn produces an average of 390,062 people per member.

Alagoas has two districts, both of which are counterminous with the two intermediate regions the state has. The first district is counterminous with Maceio, and has five members. The second district is counterminous with Arapiraca and has three. Both showed strong results for Lula.

[President Punxsutawney Phil]

Rio Grande do Norte was counted as having 3,168,027 people in the 2010 Brazilian Census. That amounts to 8.520 quotas. That rounds down to eight, post deduction of edge seats to restore a total number of 513. Rio Grande do Norte has 396,003 people per member.
This is yet another Nordeste state with an apportionment in the high single digits.
The first district is counterminous with the immediate region of Natal, and it's probably marginally larger in population than the second district, which covers the rest of the state. Both have four members. Both should be firmly and solidly left-leaning overall, and Lula did very well here.

[President Punxsutawney Phil]

The 3,483,985 people in Amazonas give it 9.369 quotas. This rounds down to 9 seats, and results in 387,109 people per member.
Given the massive difference between Manaus and the rest of the state, I chose to give Manaus its own district, and make the rest of Amazonas be another. Since Manaus is more than a majority of the population, it got the extra seat, though both would have a magnitude of at least four.
The 1st district, electing five members and counterminous with Manaus, has 1,802,014 people per the 2010 census results, and 360,403 people per member. It would very easily be right-leaning, and Bolsonaro won here with more than 60%. However, with the seat magnitude sitting at five, it is unlikely the right would ever sweep.

The 2nd district, electing four, is the largest constituency in the country by total area and also, probably, by area per member. Just as the 1st leans to the right, it would be left-leaning in equal measure. The left would be very unlikely to ever sweep here, but the left and center could probably take three of four with considerable regularity. Lula won here by an even bigger margin than Bolsonaro won the 1st. Its population was 1,681,971, resulting in 420,493 people per member. When Amazonas gains a tenth deputy, it will certainly elevate this seat to a five-seater.

[President Punxsutawney Phil]

Espirito Santo has 3,514,952 people, which translates into 9.453 quotas and 9 members. This also produces 390,550 people per member.

9 members means you can either have a four-seater and a five-seater, or three three-seaters. The population distribution makes the latter difficult, so I went with the former.
The first district is counterminous with the immediate region of Vitória, and the second district covers the rest.

The first district elects four members and the second district elects five. Both are quite conservative and Bolsonaro won here by a significant margin in both constituencies.

[President Punxsutawney Phil]

14/29 states done, and 97/513 deputies. This is every state with less than a double-digit number of deputies. 13 districts voted for Bolsonaro and 9 for Lula. The states here have a combined population just short of Texas.

[President Punxsutawney Phil]

Paraiba has 3,766,528 people, which amounts to 10.129 quotas. This gives the state ten deputies, 376,653 per person.

Given ten members, one could either have two three-seaters and one four-seater, or two five-seaters. Ultimately, the latter proved to be more practical.

The first district is counterminous with the intermediate region of Joao Pessoa. It would be the more Bolsanaro-friendly of the two. The second district is composed of the intermediate regions of Campina Grande, Patos, and Sousa-Cajazeires. Nonetheless, Lula won both of these seats.

[President Punxsutawney Phil]

After we move past Paraiba, the possible seat magnitudes begin to open up considerably. Goias, with its 16 members, can have any number of combinations, at least in theory. A lot will come down to how much people live in given intermediate regions and immediate regions in specific areas.

[President Punxsutawney Phil]

Goias has 6,003,788 people per the results of the 2010 Brazilian census, and this gives them 16.146 quotas. This in turn gives them sixteen members, 375,236 per person.

The first district of Goias is composed of just the city of Goiana, and elects four members. It likely elects three right-leaning deputies, but they could end up with two if the right-wing vote is split or strong clientelistic centrists are able to secure a seat. Bolsonaro won this district with almost 64% of the vote.

The second district is composed of the rest of the intermediate region of Goiana, and it is substantially less conservative overall. Nonetheless, it voted for Bolsonaro by probably double digits.

The third district is composed of the intermediate regions of Porangatu-Uruacu and Luziania-Aguas Lindas de Goias. It elects four members. It is probably the best hope for the left to win two seats; there are some areas within it that voted for Lula with more than 80%. It probably voted for Bolsonaro by single digits.

The fourth district is formed from the intermediate regions of Itumbiara, Rio Verde, and Sao Luis de Montes Belos-Ipara. It elects three members. Bolsonaro won here, though it's hard to tell the margin without a lot of effort.

[President Punxsutawney Phil]

The 6,248,436 people in Santa Catarina grant it 16.804 quotas, which rounds up to seventeen seats. This in turn gives them 367,555 people per member.

The first district is formed from the intermediate regions of Florianopolis and Criciuma. It elects five deputies.

The second district is formed from the intermediate region of Blumenau. It also elects five deputies.

The third district is formed from the intermediate region of Joinville. It elects three deputies.

The fourth district is formed from the intermediate regions of Lages, Chapeco, and Cacador. It elects four deputies.

It goes without saying  Bolsonaro won all four of these districts. The left would probably win one seat in each, but prospects for winning another would be a tall order.

[President Punxsutawney Phil]

Maranhao has 6,574,789 people per the 2010 Brazilian Census, and this nets it 17.682 quotas. This in turn gives it 18 deputies and 365,266 people per member.

The first district is counterminous with the four municipalities covering Upaon-Acu Island: Sao Luís, Sao Jose de Ribamar, Paco do Lumiar, and Raposa. It elects four members. Lula got 66.27% here (easy to calculate, not a lot of municipalities).

The second district covers the rest of the intermediate region of Sao Luis. It also elects four and also has a sizable left lean.

The third district is composed of the intermediate regions of Santa Ines-Bacabal and Caxias. It elects five and would be a fertile place for the PT to take two seats.

The fourth district is formed from the intermediate regions of Presidente Dutra and Imperatriz. It elects also five members and would likely elect perhaps even two PT members.

[President Punxsutawney Phil]

7,581,051 people in Para gives the state 20.388 quotas and 20 members. In turn, this produces a population/member ratio of 379,053.

The first district is counterminous with the city of Belem and elects four members. Its 2010 population is 1,393,399, 348,350 per member. Lula won here with 50.28%, leading by 4,808 votes.  

The second district covers the rest of the intermediate region of Belem and also elects four members. Bolsonaro very narrowly won the biggest municipality here (Ananindeua), by 1,572 votes, but the rest of it is mostly Lula-leaning, and by a big margin.

The third district is composed of the intermediate region of Castanhal. It elects three members. Lula won here by a big margin.

The fourth district is composed of the intermediate regions of Maraba and Breves. It elects four members. It voted for Lula by around 10 points by my estimation.

The fifth district contains the Santarem, Altamira, and Redencao immediate regions. It elects five members. It voted for Bolsonaro, but by only single digits. The PT might still win two seats here.

Running total for Lula and Bolsonaro seats: 22 Bolsonaro, 19 Lula