Early in the Pokémon franchise's life, the Poliwhirl line recieved a major push in marketing, comparable to that of series mascot Pikachu.

Mascot costumes were made of Poliwhirl for promotional events, the Pokémon Adventures manga featured Poliwhirl as one of Red's Pokémon, Poliwag was placed closely to Pikachu on the box art of Pokémon Snap, food and toy lines would near-consistently feature a member of the Poliwhirl line alongside Pikachu even when the pool of Pokémon was as limited as 3 or 4 (with exceptions primarily being ones that also lacked Pikachu), and, most famously, Poliwhirl appeared on the center of the cover of TIME Magazine's issue adressing the popularity of Pokémon.

This could be related to Poliwag being Pokémon creator Satoshi Tajiri's favourite of the original 151 Kanto species.