The "cultural backlash" thesis claims that changes in the relative size of majority and minority groups may create political resentment when previously dominant groups perceive that their core norms lose their hegemonic status. While this is an intuitive and plausible narrative, it is difficult to examine empirically because cultural and economic modernization processes often go hand in hand. We contribute to this debate by studying the Swiss referendum on the introduction of same-sex marriage ("Ehe für alle") as a rare case of revealed preferences on a purely cultural issue. In an original two-wave panel survey, we elicit respondents’ expectations about support for same-sex marriage nationally as well as within their local community before it was even clear that a referendum on this issue will take place. We re-interview the same respondents in the week after the referendum and examine the impact of corrected beliefs about the distribution of norms related to LGB rights. We provide both experimental and observational evidence on potential shifts in specific and general political attitudes, vote choice and status perceptions more generally.