(CNN)A new survey indicates there's been a sea change in public support for same-sex marriage.
In the survey, published this week by the Public Religion Research Institute (PRRI), a random sample of over 2,500 respondents from every state in the US were asked their opinion on issues including LGBTQ rights, immigration, racial justice and the pandemic.
The survey found about 70% of Americans said they support granting same-sex couples the right to marry -- the highest percentage of supporters the survey has recorded. 28% of Americans said they opposed it.
A previous American Values Survey from 2017, the last survey that asked Americans about their same-sex marriage opinions, found that 61% of respondents supported same-sex marriage while 30% opposed it.
In all but one of the religious groups polled in the 2020 survey, a majority of members said they supported same-sex marriage.That includes Protestants, Catholics, other Christians and non-Christians of all races. Religiously unaffiliated people showed the highest support for same-sex marriage at 90%.
Only white evangelicals didn't support same-sex marriage by a majority, at 34% in support.
The survey suggests public opinion is changing even among religious conservatives
Robert Jones, founder and CEO of PRRI and one of its leads on the 2020 American Values Survey, said trends in public opinion around same-sex marriage play out in a series of plateaus and jumps.
Now, support has jumped once more, and among almost every group polled -- among men and women, among white, Black and Latino Americans and among almost every religious group except white evangelicals.
It's remarkable evidence, Jones said, that same-sex marriage is no longer as controversial and divisive as it was even a few years ago.
"I think we are definitively at a place where same-sex marriage is no longer a part of the American culture wars," he told CNN. "It has become a near-consensus issue. Every age group, every racial group, every education group, both men and women and every religious group with one exception are now all in majority support."
The outliers, he said, were Republicans and white evangelicals. Though now 50% of Republicans say they support same-sex marriage, their percentage of support still jumped since the 2017 survey when 42% supported it. Jones credited this to the lack of discussion of same-sex marriage on the 2020 campaign trail.
Democrats and independents are far more supportive of same-sex marriage, at 80% and 76% respectively. Jones said that's likely due to the Democratic Party's embrace of same-sex marriage since Barack Obama's presidency.
Same-sex marriage was once a religiously divisive issue. The data shows that almost every religious group surveyed, with the exception of white evangelicals, is more accepting of it than previous polling showed, Jones said.
"There was once truth to when conservative Christians said people of faith oppose gay marriage," he said. "That is now not even plausibly true. If you look at the public opinion data, actually, people of faith as a whole, there are many more religious Americans that support [same-sex marriage]."
Support for same-sex marriage rises as time goes on
Support for same-sex marriage was low during most of the 1980s, Twenge said, hovering around 15% for much of the decade. It began to climb steadily in the 1990s, continued to climb and fall until the mid-2000s, when 50% of Americans said they supported same-sex marriage.
In more recent years, support for same-sex marriage increased fairly sharply. That's likely due to generational changes, Twenge said. Young people age into polling samples, and many of those younger people-turned-recent adults can't remember a time before same-sex marriage was legal, she said.
"It had been commonly argued that cultural attitudes don't change very quickly," she told CNN. "And attitudes around same-sex marriage are the big exception to that."
In her research, Twenge said she's found that as the US became more individualistic and Americans stopped viewing gay and lesbian people as a monolith, their attitudes toward same-sex marriage became more positive.
As individualism increased, she said, more people likely began to come out as LGBTQ, and it became more common to know an LGBTQ person. When a person has close contact with someone who belongs to a marginalized group, their attitudes often change to become more positive, she said, as was the case with support of same-sex marriage.