Story Highlights Support is up among each political party and age group

About one in four say candidates must share their views on issue

Gay marriage issue loses importance among GOP voters

WASHINGTON, D.C. -- Sixty-one percent of Americans say that marriages between same-sex couples should be recognized by the law as valid, consistent with the 58% and 60% recorded in 2015. Last year's Supreme Court decision made same-sex marriage legal nationwide -- but the issue remains contentious at state and local levels, among religious groups and within the Republican Party.

Public support for same-sex marriage has more than doubled over the past two decades. When Gallup first polled on the issue in 1996, about a quarter of Americans (27%) said such marriages should be recognized by law. Majority support was recorded for the first time in 2011, and the percentage has since grown.

The latest 61%, from the annual Values and Beliefs poll conducted May 4-8, is the highest in Gallup's trend so far by one percentage point.

With six months left until Election Day, the issue of gay marriage has been less prominent this year than in the past few presidential elections. The Supreme Court's ruling in 2015 makes the issue somewhat moot, and both Democratic candidates support it. Meanwhile, Republican front-runner Donald Trump has been fairly muted on the issue compared with some his GOP opponents, particularly those who backed a constitutional amendment defining marriage as a union between a man and a woman. While Trump says he opposes same-sex marriage, the issue does not appear on his campaign website, and he has been referred to as "the most gay-friendly Republican nominee for president ever" by the president of the Log Cabin Republicans, an organization for gay Republicans.

Trump's relatively subdued stance on the issue may be related to softened opposition from national Republicans. Four in 10 rank-and-file Republicans say same-sex marriage should be legally recognized. This is the highest support on record and is more than twice as high as the 16% found in 1996. The GOP remains the least supportive of gay marriage among the three main party groups, as strong majorities of independents (65%) and Democrats (79%) say such marriages should be recognized as valid under the law.

Majority of Oldest Americans Now Support Same-Sex Marriage

Support for gay marriage has consistently been highest among adults younger than 30 years, but support declines with each step up the age scale. At the same time, Americans in all four age groups have become more supportive since 1996.

This year marks the first time in Gallup's trend that the majority of adults aged 65 and older said gay marriage should be legal. Fifty-three percent of Americans aged 65 and older now support same-sex marriage. That is still well below the 83% support among 18- to 29-year-olds, the highest support among the age groups.

A Quarter of Adults Say Issue Could Affect Their Vote for a Candidate

Twenty-three percent of Americans say they would only vote for a candidate who shares their views on gay marriage, while 44% say it is one of many important factors. Three in 10 say it is not a major issue in terms of how they will vote. The percentage who say a candidate must agree with them on this issue to earn their vote is higher now than it was in 2004 and 2008.

Importance of Candidates' Stance on Gay Marriage in How Americans Vote Thinking about how the gay marriage issue might affect your vote for major offices, would you -- [ROTATED: only vote for a candidate who shares your views on gay marriage, consider a candidate's position on gay marriage as just one of many important factors when voting or would you not see gay marriage as a major issue]? Candidate must

share views % One of many

important factors % Not a

major issue % May 4-8, 2016 23 44 30 May 6-10, 2015 26 43 26 May 8-11, 2008 16 49 33 May 2-4, 2004 16 46 35 Gallup Poll

Americans who are opposed to gay marriage (29%) are much more likely than those in favor of it (19%) to say they would only vote for a candidate who shares their views. At the other end of the scale, 22% of gay marriage opponents compared with 32% of gay marriage supporters say it is not a major factor for their vote.

The percentage of Republicans saying gay marriage is a pivotal voting issue for them has fallen to 18% -- down from 27% as recently as last year. Among Democrats, the issue has become more important, climbing to 32% after registering 26% a year ago and just 10% in 2008.

Americans Who Say Candidate Must Share Their Views on Gay Marriage % Candidate must share views Pro-gay marriage % Anti-gay marriage % Republicans % Democrats % May 4-8, 2016 19 29 18 32 May 6-10, 2015 21 37 27 26 May 8-11, 2008 5 31 26 10 May 2-4, 2004 7 27 24 11 Gallup Poll

Bottom Line

Americans' heightened approval of gay marriage this year makes the issue a fairly straightforward one for the remaining Democratic presidential candidates. Not only do the vast majority of fellow Democrats agree with their stance, but they also have little to fear on the issue from the general electorate.

Trump might have found an ideal climate to run as a Republican with a somewhat murky record on gay marriage, given his party's tapering opposition to it and the reduced prominence of the issue to Republicans' votes. Though his opposition to gay marriage remains, he notably congratulated singer Elton John on his same-sex nuptial and even attended a gay wedding himself a year after his home state of New York legalized it. This is a marked departure from his former primary rival, Ted Cruz, who said he'd never attend a gay wedding if invited.

Attitudes on gay marriage, as well as on other LGBT issues, have been shifting since Gallup started measuring them. This has taken place across all political party and age groups, with each demographic subgroup demonstrating greater acceptance this year. With the Supreme Court's decision last year likely settling the matter of its legality, and especially since attempts by some local and state officials to defy the ruling were unsuccessful, the re-emergence of gay marriage as a divisive political issue is less likely.

Historical data are available in Gallup Analytics.

Survey Methods

Results for this Gallup poll are based on telephone interviews conducted May 4-8, 2016, with a random sample of 1,025 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia. For results based on the total sample of national adults, the margin of sampling error is ±4 percentage points at the 95% confidence level. All reported margins of sampling error include computed design effects for weighting.

Each sample of national adults includes a minimum quota of 60% cellphone respondents and 40% landline respondents, with additional minimum quotas by time zone within region. Landline and cellular telephone numbers are selected using random-digit-dial methods.

View complete question responses and trends.

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