The swap-shop's collaboration with seven other kids' websites has been a "key driver" for the brand.
During the campaign, which ran from April to June, kids could collect virtual minifigures by searching Multi Purpose Units (MPUs) on the website, picking up Swapit points along the way. Swapit created a trophy cabinet are for kids do display their collected minifigures.
To complete their online minifigure collection kids had to continue their search on the Cartoon Network, Disney, Nickelodeon, Match Doctor Who and CITV websites.
Danielle Brazier from Lego Minifigures, said: "The results of the campaign have exceeded expectations and been a key driver in helping Lego Minifigures to become the best selling toy of 2011 so far.”
"This campaign has allowed us to engage with consumers in a way that has added additional layers of play experience and value for them. Tasking kids with a virtual minifigure hunt got them thinking about the characters they wanted and prompted collecting behaviour. This strategy also enabled us to bring relevance to Lego in the digital world, which is a key focus for us moving forward."
Lee Veitch, head of advertising at Swapit.co.uk, said: “All of the MPUs are hidden in areas of the leading partner sites that reflect each Minifigue’s personality - making it much more fun for kids."