Past research demonstrates that presidential nominating conventions can exercise multiple effects on individual-level opinion; consumption of convention speeches yields opinion more favorable to the convening candidate, while exposure to partisan messaging in the surrounding information environment can trigger a general partisan bias. In this article, we demonstrate that the persuasive power of speeches made by candidates during the second convention in a given election cycle can be attenuated by exposure to information from the initial convention. Such conditional effects persist even when individual partisan affiliation and preconvention opinion are controlled. Notably, positive impressions made by candidates appear to be more impactful than negative messaging aimed at candidates by their opposition.