Called "Officially Delicious", the 拢1m campaign is based on Nestle Purina Petcare figures, which show that 5m cats already eat the brand and carries the strapline, "Officially Delicious -- five million cats can't be wrong."
Activity being carried out by Geronimo includes a roadshow tour and a direct marketing push, involving 8m promotional packs offering the chance to win prizes includes plasma screen TVs, jewellery and holidays.
The roadshow takes place in supermarkets across the UK and will include discount offers to consumers.
Sara Harris, Geronimo group account director, said: "The campaign will get people to sit up and take notice of how delicious Felix is and why it's the nation's favourite."
The campaign, which runs until the end of August, is supported by outdoor advertising, PR, radio promotions, online and print media work.
Felix brand manager Noel Clarke said: "We're very excited about the 'Officially Delicious' campaign devised by Geronimo. The integrated activities work together effectively to ensure maximum cut through among out target audience."
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