All municipal office position races in Texas are non partisan. I agree that the offenders are prolly Dems, though.
These offices are “non-partisan” until a Republican dares to enter the race.
It is only considered “non-partisan” (which technically the offices are) when all of the candidates are Democrats.
The DNC had no problem getting into the Houston Mayoral runoff election when Orlando Sanchez (R) was running against Mayor Lee P. Brown (D-Clinonista).