Tex. Pen. Code § 46.15 generally prohibits a person from bringing a firearm onto the premises of a polling place. However, this prohibition does not apply to a peace officer, regardless of whether the police officer is on or off duty.
The legislation allowing open carry of handguns, does NOT change the law as it pertains to guns in the polling place; thus no one except licensed peace officers may carry handguns into the polling place.