Can Demographic Homophily Enhance the Effectiveness of Virtual Influencer Marketing? An Experimental Study of Age, Race, and Gender Congruence in Pro-Environmental Campaigns

This study investigates how demographic homophily between audiences and virtual influencers (VIs) shapes the effectiveness of pro-environmental campaigns. A between-subjects online experiment employing a 2 (age homophily: outgroup vs. ingroup) × 2 (racial homophily: outgroup vs. ingroup) × 2 (gender homophily: outgroup vs. ingroup) factorial design was conducted with 430 U.S. social media users, who were exposed to simulated Instagram posts featuring VIs promoting an eyewear brand’s sustainability initiative. Grounded in Social Identity Theory, the findings reveal that age, race, and gender homophily exert both direct and interactive effects on attitudes toward VIs and green behavioral intentions, with the strongest responses emerging when all dimensions align. Moreover, wishful identification fully mediated the effects of homophily on both outcomes, while perceived similarity influenced only green behavioral intention. The study extends identity-based perspectives to virtual communication and provides actionable insights for practitioners seeking to strategically leverage VIs in social marketing campaigns.