The national survey by the Pew Research Center, conducted May 1-5 among 1,504 adults, finds that support for same-sex marriage continues to grow: For the first time in Pew Research Center polling, just over half (51%) of Americans favor allowing gays and lesbians to marry legally. Yet the issue remains divisive, with 42% saying they oppose legalizing gay marriage. Opposition to gay marriage – and to societal acceptance of homosexuality more generally – is rooted in religious attitudes, such as the belief that engaging in homosexual behavior is a sin.

At the same time, more people today have gay or lesbian acquaintances, which is associated with acceptance of homosexuality and support for gay marriage. Nearly nine-in-ten Americans (87%) personally know someone who is gay or lesbian (up from 61% in 1993). About half (49%) say a close family member or one of their closest friends is gay or lesbian. About a quarter (23%) say they know a lot of people who are gay or lesbian, and 31% know a gay or lesbian person who is raising children. The link between these experiences and attitudes about homosexuality is strong. For example, roughly two-thirds (68%) of those who know a lot of people who are gay or lesbian favor gay marriage, compared with just 32% of those who don’t know anyone.