This paper analyses '?debate threads' of the UDF, Jeunes Populaires (UMP) and D?sirs d'avenir web forums, between October 2006 and April 2007. It shows that discursive activities are, in decreasing order, the 'disputes'?, the 'proposal debates'?, the 'proposal messages'? and the 'criticism and support of candidates'?. The 'proposal debates'?, mainly found in D?sirs d'Avenir, are very rare in Jeunes Populaires. Despite their high level of controversy, some changes in the participants' opinions do occasionally occur during these debates. Yet the PS and UMP candidates' programmes do not seem to be linked to these opinions.