I suspect that the majority of visitors to Turkey have no idea how it works on election days in relation to the sale of alcohol.
In previous years most bars in the tourist areas started to sell alcohol as soon as the polls closed, and some prior to that. One year there were a lot of folks drinking beer out of paper Coca Cola cups in the Paspatur
The Polis and Zabita in Fethiye have usually taken a pragmatic view when it comes to tourists, alcohol and election day, a sentiment I suspect that came from above. Places like the Jiva, Letoon etc wont have many Turkish guests as traditionally Turks return to their home town/village city to vote.
I'd be surprised if the ban was rigidly enforced once the voting stations close, but then again, nothing about Turkey ever really surprises me any more so maybe it will!
JF