Objective We hypothesize that priming a shared in‐group identity can lead to openness to attitudinal change, even on highly polarized issues. Specifically, we test whether priming a shared identity as a religious person can generate willingness to voice support for same‐sex marriage. Methods We conduct a randomized survey experiment using the SocialSci platform, exposing religious and secular respondents to religious and anonymous primes about same‐sex marriage. Results Individuals who are religious and who are exposed to the treatment prime are more likely to say that they support marriage equality and would vote for a ballot initiative in their state that would allow same‐sex marriage. Conclusion Despite widespread opposition to marriage equality among people of faith, having that religious identity primed through an elite religious cue has a significant and often dramatic effect on attitudes toward marriage equality.