Previous research has suggested that exposure to political advertising is generally informative and may even reduce information gaps between the most and least aware in society, but does not produce large shifts in candidate preference. Drawing on extant models of opinion change, we predicted that the informational benefits of political ads would vary by level of awareness, such that the most aware would experience the largest gains, especially when they are asked to make inferences about issues not explicitly discussed in the ad. Further, we predicted that the most aware would use information in advertisements as a substitute for other kinds of information seeking, while the least aware would be relatively unmotivated to seek out new information, regardless of exposure. Finally, the least aware would be more susceptible to persuasion via ads than the most aware would be. Experimental evidence confirmed these predictions.