Support for same-sex marriage has been on the rise over the past 15 years. Across four Pew Research Center surveys this year, 48% of Americans say they favor allowing gays and lesbians to marry legally, while 43% are opposed. Just four years ago, in the 2008 election cycle, 51% opposed making same-sex marriages legal and 39% supported it.

While support has grown in all regions of the country, it is far stronger in some than in others. In New England, 62% favor same-sex marriage, while 29% oppose it. People in the South express greater opposition. A majority (56%) in the central Southern states such as Alabama, Kentucky, Louisiana, Oklahoma and Texas oppose same-sex marriage, while about a third (35%) favors it — amounting to a 27 percentage point difference compared with New England.

Attitudes toward gay marriage in the South are comparable to where the country as a whole was a decade ago.

In the mid-Atlantic, 57% favor and 34% oppose allowing gay marriage. Opinions among those on the West Coast are similar (54% favor, 37% oppose). In the Midwest, opinion is more evenly divided (46% favor, 44% oppose).

On Election Day 2012, ballot measures legalizing same sex marriage were approved in Maine, Maryland and Washington state. The recent gains come after years of electoral setbacks for advocates of same-sex marriage. More than 30 states have prohibited gay marriage by popular vote over the past 15 years. Read More