Though previous evaluations of "The Real Cost" anti-smoking campaign demonstrate effects on anti-smoking beliefs and behaviors, results rely on self-reported recall as a measure of exposure and are thus open to reverse causation concerns. Exogenous measures of exposure, assessed independently of outcomes, support stronger causal inferences. In this study, we examined the relationship between Target Rating Points (TRPs) for specific ads available over four-week periods and anti-smoking beliefs in a national sample of adolescent nonsmokers and experimenters (n = 4,780). Results demonstrate positive relationships between TRPs for ads targeting two of four belief categories tested (Control and Chemical; p < .05) and targeted-belief endorsement. Furthermore, moderation models indicate that ad-specific TRPs affected targeted beliefs more than non-targeted beliefs for those Control- and Chemical-targeted ads (p < .01). Findings support a claim of campaign effects while reducing concerns about reverse causal direction and the influence of unmeasured confounders.