This paper explores whether witnessing an Intelligent Virtual Agent (IVA) in what appears to be a socially engaging discussion with a Confederate Virtual Agent (CVA) prior to a direct interaction, can prime a person to feel and behave more socially engaged with the IVA in a subsequent interaction. To explore this social priming phenomenon, we conducted an experiment in which participants in a control group had no priming while those in an experimental group were briefly exposed to an engaging social interaction between an IVA and a nearby CVA (i.e. a virtual actor). The participants primed by exposure to the brief CVA-IVA interaction reported being significantly more excited and alert, perceiving the IVA as more responsive, and showed significantly higher measures of Co-Presence, Attentional Allocation, and Message Understanding dimensions of social presence for the IVA, compared to those who were not primed.