Soft & Gentle is running a five-pronged online strategy that will also see standard pop-ups, banners, sponsored text alerts to Channel 4's T4 show database and sponsorship of an online competition.
Entrants can submit their own 'Soft and Gentle' moments to win prizes ranging from a trip to the Dawson's Creek set to props from the show.
It will be promoted on-air to encourage entries, and the winner will be announced live on T4 Sunday.
The online campaign forms part of Soft & Gentle's current sponsorship of teen soap Dawson's Creek on E4 and of T4 in September.
Ruth Brownlee, commercial development controller at Channel 4 Interactive, said: "Dawson's Creek is a perfect brand fit for Soft & Gentle. Its willingness to extend the sponsorship online complements the television work and allows us to create something of real value to both the user and Colgate-Palmolive."