Held concurently alongside the first Jones-Shafroth act Elections in Puerto Rico (1917), the Prohibition Plebiscite that year returned a landlside for the forces in Favor of a constitutional amendment for the Prohibition of Alcohol in Puerto Rico.
Occuring before the U.S.'s prohibition on the mainland, the Yes campaign focused on the public morality of alcohol, such as the evils of drunkeness.
While the No Campaign focused on protecting the people's ability to choose to drink, the free market, and the taxes and tarriffs that could be used to bring money to the PR Treasury thanks to the Export of Rum.
It should be noted that neither the Yes, nor the No Campaigns had institutional support from any of the Major parties at the time(Partido Unionista, Partido Republicano(PR) ni el Partido Socialista Obrero).
Looking at the coalitions, while not exactly a 1-1 Correlation, the NO Campaign found it's best whowings in the At the time Republican areas in the south west, while the yes campaign found it's best showings in the at the time Predominantly Union Areas of Puerto Rico such as in Caguas and the East of the Island more generally.
Looking at Senate Districts, Yes to Prohibition/Implementing the Dry Law won 5/7 Districts, and No to Prohibition/Implementing the Dry Law won 2/7 Districts
And lastly, looking at House of Representative's Districts, Yes to Prohibition/Implementing the Dry Law won 24/35 Districts, and No to Prohibition/Implementing the Dry Law won 11/35 Districts.