Apparently a majority of people believe that Trump will win less than 55% in Hamilton County. As a reminder here are the performances of different republican candidates in 2018.
State Treasurer :
R : 62.46%
Secretary of State :
R : 59.41%
State Auditor :
R : 60.28%
House of Representatives :
R : 61.10%
Senate :
R : 52.38%
I would also highlight the fact that in every of these races the republican candidate did better in Hamilton county than statewide (or districtwide for the US House)
Most people don't pay attention to lower-level row offices. Plus, the candidates that did run in those races weren't particularly strong.
Poll
