As far as I know, campaigning is not allowed at a polling station and within a certain radius around them. How strict is it what counts as campaigning in that context? For example, from what a news report I just watched, it looked to me as if one of the candidates of a current election cast their vote while wearing a piece of clothing prominently showing their catchphrase campaign slogan (apparently without any consequences).
On the one hand, a candidate can hardly avoid showing e.g. their face which is the same as on their ads. On the other hand, I suppose that anybody else would be asked to remove or cover such a slogan.