This book presents the main results of an electoral panel survey which is both unique and innovative in French electoral research and among the most detailed panel study in Europe. The survey was conducted among a sample of 1,846 French voters interviewed on four waves during the 2007 presidential and legislative elections in the context of Nicolas Sarkozy's victory. The analysis provides an understanding of how decisions on voting are made, the process of electoral decision-making and also the mechanisms used by the voter to make a choice and attempts to identify the social, political, and psychological factors at play.