The American public is almost evenly divided on the issue of gay marriage: 46% favor allowing gays and lesbians to marry legally, while 44% are opposed. Public views on this issue have changed gradually over time; five years ago – in 2006 – 35% of people supported gay marriage while 56% were opposed. Fifteen years ago – in 1996 – just 27% favored gay marriage while 65% were opposed. But support has grown steeply recently, culminating in a nine point bumpin just the past two years (37% in 2009, 46% today).

Different generations of Americans have starkly different views on some of the social changes occurring in the country today, including same-sex marriage. Almost six-in-ten Millennials (59%) support gay marriage, compared to just a third (33%) of members of the over-65 Silent generation. About four-in-ten Boomers (42%) support legalizing same-sex marriage, as does half (50%) of Generation X.

The gradual shift in public opinion on same-sex marriage largely reflects the changing views of successive generations. Over the last 15 years, each generation has been more supportive of gay marriage than its predecessor. As the younger generations make up a larger share of the public, the balance of opinion has shifted.

But the bump in support for gay marriage has been more pronounced in recent years because of significant attitude changes within generational groups. As recently as 2009, just 23% of Silents supported gay marriage; now 33% share this view. Notable increases in the past two years have also been seen among Boomers (from 32% to 42%), Gen Xers (from 41% to 50%) and Millennials (from 51% to 59%). Read More

Russell Heimlich  is a former web developer at Pew Research Center.