What if the six states admitted to the Union under Benjamin Harrison were admitted as a single state?

AUTHOR’S NOTE: This blog post is a preview of a future self-published political eBook, to be written by the author of this blog post under the pen name Aaron Apollo Camp and tentatively titled Gerrymandering the Senate: How Benjamin Harrison’s 19th Century Political Power Grab Affects American Politics Today.

Last month, a Reddit user operating under the screen name u/BroIBelieveAtYou, whose real name is unknown, posted this map of the theoretical State of Harrison, consisting of the territory of the current states of Idaho, Montana, North Dakota, South Dakota, Washington, and Wyoming. David Montgomery of The Atlantic‘s CityLab tweeted the map not long after it was uploaded to Reddit:

Harrison includes all six states admitted to the Union during the presidency of Benjamin Harrison, a Republican who served as the nation’s 23rd President from 1889 to 1893. There doesn’t appear to be any major inaccuracies in the map itself, although it’s important to note that whoever created the map hypothesized that the City of Helena, currently in Montana, would be chosen as Harrison’s state capital.

In an information blurb provided in the map under the heading “Federal Political Consequences”, the creator of the map noted that Harrison becoming a single state “would obviously cause the Republicans to lose the U.S. Senate federally”. That’s not a clearly true statement, unfortunately for left-of-center people like me.

If Harrison were to become a single state, Harrison would receive two U.S. Senators, just like any other state in the Union. However, as the area covered by Harrison is currently covered by six different states, the area covered by Harrison is currently represented by 12 U.S. Senators. As a result, the area covered by Harrison would lose ten U.S. Senators, and the U.S. Senate’s total number of seats would, correspondingly, decrease by ten, from 100 seats to 90 seats.

The current U.S. Senate has a total of 100 seats, with 53 seats held by Republicans and 47 seats held by Democrats; this figure counts two seats held by U.S. Senators elected as independents as Democrats, as both independent Senators are currently members of the Senate Democratic Caucus. The area covered by Harrison is currently represented by nine Republicans and three Democrats. If Harrison were to become a single state, and Harrison sent one Democrat and one Republican to the U.S. Senate, that would represent a net loss of two seats for the Democrats and eight seats for the Republicans. Under that hypothetical scenario, control of the U.S. Senate would be tied between the two major parties, with each major party holding 45 seats. As the Vice President of the United States, currently Republican Mike Pence, has the tie-breaking vote power as President of the U.S. Senate, this would result in a U.S. Senate controlled by Republicans due to Pence’s tie-breaking vote, absent the agreement to, and implementation of, a formal power-sharing agreement. If the Democrats were to win both of Harrison’s U.S. Senate seats, and no other U.S. Senate seat in a state not affected by Harrison becoming a single state were to be controlled by a different political party than the political party that currently controls the seat in question, Democrats would hold a 46-44 majority in the Senate. However, Harrison would likely not be a stronghold for either major political party, and, if anything, the state would likely be slightly Republican-leaning.

A book of spreadsheets containing population, U.S. House of Representatives apportionment, and 2016 U.S. Presidential Election analysis of the theoretical State of Harrison can be found here. As you can tell from the spreadsheets, there is another error in the Federal Political Consequences blurb in the map; the additional error is about the 2016 U.S. Presidential Election. While Trump would have carried Harrison in 2016 if Harrison was a single state in 2016 (on a related note, Harrison would have 18 electoral votes if it were a single state today), Trump’s margin of victory in Harrison in 2016, in terms of percentage of the total popular vote in Harrison, would have been slightly less than 3% of the total popular vote in Harrison, although the estimate provided in the map for the raw vote margin in Harrison is accurate to the nearest ten thousand.