You do not need approval from Council for an election display on the footpath, as long as you comply with the relevant conditions.
An election sign is a temporary advertisement advocating for or against the election of a candidate or candidates, or a registered political party in respect of a federal, state or local government (Brisbane City Council) election campaign. There are different requirements for election signs on private property, public property, polling locations and Mobile Vehicle Election Signs.
Election sign enforcement
Find out the guidelines for political parties, candidates and elected representatives by downloading: