One of the most popular forms of humour on the Internet is memes. Given the identity construction motif that is associated with memes, agents of memes select targets outside the in-group and criticise the targets' behaviour for ideological purposes. This study examines the patterns of humour evidenced in the deployment of Internet memes (both verbal and visual) in the online campaign discourse of the 2015 presidential election in Nigeria. Data for the study consist of Internet memes produced and disseminated during the presidential election campaign between December 2014 and March 2015. Considering Archakis and Tsakona's view that humour can be a very efficient means of identity construction, the study applies Van Dijk's socio-cognitive model with particular reference to the theoretical concept of the 'ideological square', which encapsulates the twin strategies of positive 'in-group' description and negative 'out-group' description. This theoretical approach is complemented with Neuendorf et al.'s taxonomy of theoretical perspectives on humour. The study reveals that the memes deployed in the presidential election online campaign discourse largely serve subversive purposes to detract greatly from the electoral value of the targets. In terms of the reinforcing function of humour, however, serious socio-political issues were raised to express the public's worries and desires in a bottom-up communication flow.