FiveThirtyEightSERIESThe Gerrymandering Project
PUBLISHED JAN. 24, 2018 AT 4:59 PM
The Atlas Of Redistricting
By Aaron Bycoffe, Ella Koeze and David Wasserman
There’s a lot of complaining about gerrymandering, but what should districts look like? We went back to the drawing board and drew six different congressional maps for the entire country. Each map has a different goal: One is designed to encourage competitive elections, for example, and another to maximize the number of majority-minority districts. See how changes to district boundaries could radically alter the partisan and racial makeup of the U.S. House — without a single voter moving or switching parties. How we did this >>.[a]
GO TO: Nation Alabama Arizona Arkansas California Colorado Connecticut Florida Georgia Hawaii Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina Ohio Oklahoma Oregon Pennsylvania Rhode Island South Carolina Tennessee Texas Utah Virginia Washington West Virginia Wisconsin PARTISAN GOALS OTHER GOALS
Show current district boundaries
Gerrymander districts to favor Republicans
Gerrymander districts to favor Democrats
Match partisan breakdown of seats to electorate
Promote highly competitive elections
Maximize number of majority-minority districts
Make district shapes compact (using an algorithm)
Make districts compact while following county borders
← National map
Alabama’s current congressional district boundaries
How often we’d expect a party to win each of Alabama’s 7 seats over the long term — not specifically the 2018 midterms — based on historical patterns since 2006
100% D100% RBirminghamBirminghamMobileMobileHuntsvilleHuntsvilleMontgomeryMontgomery
| USUALLY DEMOCRATIC DISTRICTS | HIGHLY COMPETITIVE DISTRICTS | USUALLY REPUBLICAN DISTRICTS | |
|---|---|---|---|
| Current | 1 | 0 | 6 |
| Current | 1 | 0 | 6 |
About the current map
These are the current congressional district boundaries, shaded by how likely each is to be represented by a party over the long term. This is not a forecast of the 2018 midterm elections.
The politics of Alabama’s maps
Party probabilities
Every district by the chance it will be represented by either party
| DEM. CHANCES | GOP CHANCES | |
|---|---|---|
| 100%90%80%70%60%50%60%70%80%90%100% | ||
| Proportionally partisan | ||
| Majority minority | ||
| Democratic gerrymander | ||
| Highly competitive | ||
| Compact (borders) | ||
| Current | ||
| Republican gerrymander | ||
| Compact (algorithmic) | ||
Expected seats by party[d]
The expected number of seats controlled by Democrats and Republicans, based on their long-term likelihood of winning each district
| DEMOCRATSEVEN SPLITREPUBLICANS |
|---|
| 1.95.1 |
| 1.95.1 |
| 1.95.1 |
| 1.65.4 |
| 1.15.9 |
| 1.06.0 |
| 1.06.0 |
| 0.76.3 |
Ranking Alabama’s maps
How the maps compare on district competitiveness, minority makeup, compactness, respect for local borders and the efficiency gap, an attempt to gauge how politically gerrymandered a set of districts is
Efficiency gapA measure of “wasted” votes, by the size of the advantage and which party it favors
| Dem. gerrymander | D+4% |
| Majority minority | D+4% |
| Proportional | D+4% |
| Compact (borders) | D+6% |
| Competitive | D+6% |
| GOP gerrymander | R+10% |
| Current | R+10% |
| Compact (algorithmic) | R+17% |
Competitive districtsNumber of districts in which both parties have at least a roughly 1-in-6 chance of winning
| Compact (algorithmic) | 2 |
| Competitive | 2 |
| Compact (borders) | 2 |
| Current | 0 |
| Proportional | 0 |
| Majority minority | 0 |
| GOP gerrymander | 0 |
| Dem. gerrymander | 0 |
Majority-nonwhite districtsNumber of districts in which a majority of the voting-age population is nonwhite
| Proportional | 2 |
| Majority minority | 2 |
| Dem. gerrymander | 2 |
| Current | 1 |
| GOP gerrymander | 1 |
| Competitive | 1 |
| Compact (algorithmic) | 0 |
| Compact (borders) | 0 |
County splitsNumber of times a map splits counties into different districts
| Compact (borders) | 5 |
| Dem. gerrymander | 8 |
| GOP gerrymander | 8 |
| Majority minority | 8 |
| Proportional | 8 |
| Current | 8 |
| Competitive | 12 |
| Compact (algorithmic) | 34 |
Compactness rankRank by the [e][f][g], from least (best) to greatest (worst)overall geographic compactness of its districts
| Compact (borders) | 1 |
| Compact (algorithmic) | 2 |
| Dem. gerrymander | 3 |
| Majority minority | 3 |
| Proportional | 3 |
| Competitive | 6 |
| GOP gerrymander | 7 |
| Current | 7 |
Breaking down Alabama’s current map by race
The racial makeup of each district, and each district’s likelihood of being represented by a member of a racial minority, based on election results since 2006.
WHITEAFRICAN AMERICANHISPANIC/LATINOASIAN/PACIFIC ISLANDEROTHER
| SHARE OF POPULATION BY RACE | CHANCE OF BEING REPRESENTED BY A … | |||||
|---|---|---|---|---|---|---|
| DISTRICT | MAJORITY RACE | 0% 50% 100% | MINORITY MEMBER | DEMOCRAT | REPUBLICAN | |
| 1st | White | 9% | <1% | >99% | ||
| 2nd | White | 10% | <1% | >99% | ||
| 3rd | White | 6% | <1% | >99% | ||
| 4th | White | <1% | <1% | >99% | ||
| 5th | White | 3% | <1% | >99% | ||
| 6th | White | 1% | <1% | >99% | ||
| 7th | African-American | 95% | >99% | <1% | ||
All demographic data from the 2010 census. Six of the seven alternative congressional district maps were drawn using Dave’s Redistricting App, a free online tool for experimenting with political boundaries. Its creator, Dave Bradlee, modified the app to make this project possible. The seventh map comes from software engineer Brian Olson, who wrote an algorithm to draw districts with a minimum average distance between each constituent and his or her district’s geographic center. Read more about how we drew these maps and how we are evaluating them in our methodology.[h]
Get the data on our GitHub page[i]
Additional contributions from Nate Silver and Julia Wolfe
Sources: Ryne Rohla/Decision Desk HQ, U.S. Census Bureau, Brian Olson
More from this series
METHODOLOGY
We Drew 2,568 Congressional Districts By Hand. Here’s How.
PODCAST & VIDEO
ESSAY
Hating Gerrymandering Is Easy. Why Is Fixing It So Hard?
COMMENTS
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