Extensive research has focused on the role of attitude toward the ad (AAd) in advertising effectiveness, but recent meta-analyses have provided limited evidence of a strong and consistent link between AAd and attitude toward the brand (ABrand). Such findings challenge traditional beliefs about how AAd translates into ABrand and what leads to effective advertising. A key limitation of prior research is a failure to distinguish between the brand message and its delivery method in advertising studies. While strategy research emphasizes the importance of product differentiation, studies on advertising’s impact on market outcomes have largely ignored the presence of a brand-differentiating message (BDM), despite some evidence that it is associated with ad effectiveness. This study conducts a longitudinal analysis of BDM’s impact on ad awareness, brand liking, consideration, purchase intention, and market penetration during a decade of Super Bowl advertising, examining 280 brand-level observations of commercials coded for over 60 content features over a period of 61 days after the Super Bowl (N = 17,080). Results from a difference-in-difference model challenge conventional advertising models, underscoring BDM’s profound effects and its interaction with other ad message content and delivery factors. The study clarifies the relationship between ad liking and various measures of consumer response by demonstrating that ad liking influences these measures only when a differentiating product message is present. The paper concludes with a discussion of why this interaction is present and its implications for advertising content.