Most public opinion attitudes in the United States are reasonably stable over time. Using data from the General Social Survey and the American National Election Studies, I quantify typical change rates across all attitudes. I quantify the extent to which change in same-sex marriage approval (and liberalization in attitudes toward gay rights in general) are among a small set of rapid changing outliers in surveyed public opinions. No measured public opinion attitude in the United States has changed more and more quickly than same-sex marriage. I use survey data from Newsweek to illustrate the rapid increase in the 1980s and 1990s in Americans who had friends or family who they knew to be gay or lesbian and demonstrate how contact with out-of-the-closet gays and lesbians was influential. I discuss several potential historical and social movement theory explanations for the rapid liberalization of attitudes toward gay rights in the United States, including the surprising influence of Bill Clinton’s 1992 presidential campaign.