I. Attitudes on Same-sex Marriage Steady in 2015

Across 2015, the year that saw same-sex marriage become legal in all 50 states following the landmark Obergefell v. Hodges Supreme Court decision in June, public opinion on same-sex marriage remained remarkably stable. Based on interviews with more than 42,000 Americans conducted between May and December 2015, PRRI finds that 53% of Americans support allowing gay and lesbian people to legally marry, while 37% are opposed.

In surveys conducted during May 2015, the month before the Supreme Court decision, 53% of the public on average supported same-sex marriage. Weekly tracking polls showed no significant shift in opinion as a result of the court decision, with the June average showing 55% support and the July average showing 53% support.

Same-sex Marriage by Age and Gender

Few attributes are more important in structuring attitudes on same-sex marriage than age. Generally, there is an inverse relationship between support for same-sex marriage and increasing age, but the relationship is not uniformly linear. Among younger American adults, from those in their late teens to mid-forties, majorities support same-sex marriage, with the strength of support generally decreasing as age increases. For example, 74% of 20-year-olds support same-sex marriage, compared to 53% of 45-year-olds.

Among Americans in their late forties to late sixties, the linear relationship between support for same-sex marriage and age plateaus, with Americans in this group roughly divided on the issue. Forty-nine percent of 50-year-olds support same-sex marriage, a number that is similar to support among 68-year-olds (48%). The linear relationship between support for same-sex marriage and age picks up again among Americans who are 70 years of age or older. For example, 41% of 70-year-olds support same-sex marriage, compared to only 33% of those aged 80 and older.

The correlation between age and support for same-sex marriage is also striking when comparing age cohorts. More than seven in ten (71%) young adults (age 18 to 29) favor allowing gay and lesbian couples to marry, compared to roughly four in ten (41%) seniors (age 65 and older). Notably, however, there is no age group in which a majority opposes same-sex marriage. Only half (50%) of seniors oppose same-sex marriage, although one in ten (10%) offer no opinion on the issue.

Women are somewhat more likely to support same-sex marriage than men, a pattern that is consistent across generations. Overall, nearly six in ten (57%) women, compared to only half (50%) of men, favor allowing gay and lesbian couples to marry legally. Among young adults, roughly three-quarters (74%) of women and two-thirds (67%) of men favor same-sex marriage.1 The age gap is roughly the same size among seniors. More than four in ten (43%) senior women, but only 36% of senior men, support same-sex marriage.

Same-sex Marriage by Race and Ethnicity

Among racial and ethnic groups, Americans who identify as Asian or Pacific Islander (API) are the most supportive of same-sex marriage. Nearly two-thirds (64%) of API Americans favor allowing gay and lesbian couples to marry. Similar to the public overall, majorities of white Americans (56%), Hispanic Americans (54%), and mixed-race Americans (55%) favor same-sex marriage. Black Americans are roughly divided in their opinions about same-sex marriage (43% favor, 48% oppose). There is a strong generational divide among black Americans, with 63% of black Americans under the age of 30 supporting same-sex marriage, compared to only 31% of black seniors.

Same-sex Marriage by Religious Affiliation

The strongest supporters of same-sex marriage continue to be members of non-Christian religious traditions and religiously unaffiliated Americans. At least three-quarters of Buddhists (85%), the religiously unaffiliated (78%), and Jewish Americans (76%) favor allowing gay and lesbian to marry. Solid majorities of Hindus (66%), Orthodox Christians (61%), white mainline Protestants (59%), white Catholics (59%), and Hispanic Catholics (56%) also express support for same-sex marriage. In contrast, majorities of black Protestants (54%), Hispanic Protestants (59%), Mormons (66%), white evangelical Protestants (67%), and Jehovah’s Witnesses (72%) oppose allowing gay and lesbian couples to marry. Muslims are divided in their opinions over same-sex marriage (41% favor, 45% oppose).

Even among the most ardent opponents of same-sex marriage, stark generational divisions persist. Young white evangelical Protestants, for example, are divided over same-sex marriage, with roughly equal numbers expressing support (47%) and opposition (49%). In contrast, roughly three-quarters (74%) of white evangelical Protestant seniors oppose same-sex marriage. There are only modest generational differences among Mormons. Nearly six in ten (58%) younger Mormons oppose same-sex marriage, as do seven in ten (70%) Mormon seniors.

Same-sex Marriage by Political Affiliation

The views of Republicans and Democrats on same-sex marriage are near mirror opposites. Roughly two-thirds (66%) of Democrats favor allowing gay and lesbian couples to marry, while fewer than three in ten (27%) are opposed. Conversely, nearly six in ten (59%) Republicans oppose same-sex marriage, while about one-third (34%) support it. Political independents are closer to Democrats than Republicans on this issue: a majority (58%) favor allowing gay and lesbian couples to marry.

However, ideology impacts Republicans and Democrats alike on the issue of same-sex marriage. While about eight in ten (82%) liberal Democrats and roughly six in ten (61%) moderate Democrats support same-sex marriage, only about four in ten (41%) conservative Democrats say the same. Among Republicans, a majority of liberal (55%) and moderate (54%) Republicans favor same-sex marriage, compared to only one-quarter (25%) of conservative Republicans. Approximately seven in ten (68%) conservative Republicans oppose same-sex marriage.

Even among the most ardent opponents of same-sex marriage, stark generational divisions persist. Young white evangelical Protestants, for example, are divided over same-sex marriage, with roughly equal numbers expressing support (47%) and opposition (49%). In contrast, roughly three-quarters (74%) of white evangelical Protestant seniors oppose same-sex marriage. There are only modest generational differences among Mormons. Nearly six in ten (58%) younger Mormons oppose same-sex marriage, as do seven in ten (70%) Mormon seniors.

Same-sex Marriage by Geography

Support for same-sex marriage varies significantly by region. Residents of the Northeast express the highest support, with more than six in ten (63%) favoring same-sex marriage. A majority of Americans living in the West (59%) and the Midwest (54%) also favor same-sex marriage, while residents of the South are divided on the issue (46% favor, 45% oppose).

In the South, however, there are significant generational divisions on the issue. Two-thirds (67%) of young adults in the South support same-sex marriage, compared to roughly one-third (32%) of seniors. Nearly six in ten (58%) Southern seniors express opposition to same-sex marriage.

Unsurprisingly, the states with the highest support for same-sex marriage tend to be clustered in the Northeast, while the states with the lowest support can be found predominately in the South. Massachusetts—the first state in the nation to legalize same-sex marriage in 2004—registers the highest support for the policy today (76% favor). Support for same-sex marriage is robust across New England with approximately seven in ten residents of New Hampshire (73%), Connecticut (70%), Rhode Island (69%), and Vermont (69%) expressing support.

Notably, there are only five states in which a majority of residents oppose same-sex marriage. Support for same-sex marriage is lowest in the Deep South: just one-quarter (25%) of Mississippi residents and one-third (33%) of Alabama residents favor same-sex marriage. Sixty-five percent of Mississippi residents and 60% of Alabama residents oppose same-sex marriage. Opposition to same-sex marriage also reaches a majority in three other states: Arkansas (57%), South Dakota (57%), and Tennessee (56%).