The Sources of Rising Support for Same-Sex Marriage

Using data on 116,816 respondents from 91 national surveys conducted between 2000 and 2009, this paper assesses how rapidly support for same-sex marriage has increased in the past decade; whether cohort replacement, other population changes, or individual attitude explains the rising support; and whether time trends, cohort effects, and mind-changing vary meaningfully across groups. Support is growing at a rate of about one percentage point per year. Cohort replacement explains about one-third of the increase, and religious and racial changes in the population explain another one-sixth. About half the change appears to be due to individuals changing their minds in favor of same-sex marriage. Time trends are not uniform. Attitudes are increasingly polarized along party, gender, and race/ethnicity lines. Ideological and religious differences remain very strong but do not seem to be widening. The differences in time trends probably arise from differences in individual attitude change, as cohort effects are similar across sub-populations