Support for same-sex marriage hits all-time high in U.S. An expert explains why.

Public support for legal same-sex marriage is at an all-time high in the U.S., according to a new Gallup poll, at 70 percent overall — an increase of 10 percentage points since the U.S. Supreme Court legalized same-sex marriage across the nation in 2015.

And, for the first time since Gallup began this poll, in 1996 — when the overall approval rating was at 27 percent — a majority of Republicans (55 percent) have expressed support. That’s compared to 73 percent of independents and 83 percent of Democrats, a number that has remained relatively the same in recent years, suggesting it may have hit a ceiling for now, Gallup notes in a news release.

While all age groups are the most supportive than ever before, a younger group means higher support, as may be expected — with 84 percent of young adults (ages 18 to 34), 72 percent of middle-aged adults (ages 35 to 54) and 60 percent of older adults (age 55 and older) in favor.

“It’s wonderful,” says attorney and activist Evan Wolfson, who spearheaded the same-sex marriage movement as founder of the now-defunct Freedom to Marry, regarding the record-high 70 percent approval. Wolfson, whose tenacity in the fight was documented in the film The Freedom to Marry, spoke with Yahoo Life to share insights on how we got here.

“We always viewed marriage as both an important goal and as a strategy for effecting change,” Wolfson recalls about the approach to altering hearts, minds and the law. “It was worth fighting for in itself, and I believed there was a pathway to getting there.” But he also believed all along that by working to win marriage equality, “we would be claiming the vocabulary of love, family, inclusion and dignity that would be an engine of transformation … and that it would enable us not only to win marriage but to advance on all other fronts — and that it would propel us forward in larger ways.”

The power of a conversation

In figuring out the reasons behind rising support, it’s easy to believe that it’s due to more and more people coming out, leading more straight people to be able to say they know someone who is gay. Even President Bill Clinton in 1996 — as he was signing the Defense of Marriage Act (DOMA) into law, punting marriage equality to the states — noted it was important that everyone get to know more gay people, Wolfson recalls.

“We used to think: All we need to do is come out,” he says. “As we dug deeper into the strategy of changing public opinion, what we learned is that the conventional wisdom obscured a kernel of truth within it — it’s not just knowing someone who’s gay, it’s having a conversation with someone who’s gay. … What we really needed to do was talk about who gay people are, why marriage matters, what are our shared values, then helping people connect their values to these other people.”

Judging by the latest numbers, those connections have continued to take place, regardless of political parties.

Swaying public opinion: a complex strategy from the start

Freedom to Marry’s strategy, Wolfson explains, was to win at the Supreme Court level after having created a climate change based on three tracks. It was crucial that the approach was well thought out because, as he notes, the question of marriage equality had gone before U.S. Supreme Court before — in the early 1970s, in the aftermath of the Stonewall uprising (a rallying point for LGBTQ rights in 1969), with couples from Minnesota, Kentucky and Washington challenging their state’s refusal to grant them marriage licenses. But all had been rejected. “How do we get the Supreme Court to say yes when they had already said no?” Wolfson recalls the activists pondering. “Litigation, we argued, would not be sufficient.”

The first track of the plan was to build “a critical mass of states where we could get married,” which would politically, legally and electorally set the stage for the federal challenge. “When we started, we were at zero,” he notes, before the first victory — in Hawaii, in 1996 — when the Gallup poll was at 27 percent support. “It wasn’t bad for having just begun the conversation, but wasn’t critical mass for victory. We needed to grow that number,” Wolfson says, which was the second track of the plan. That’s where the campaign of conversations came in, to great effect.

The third was “to tackle and end the federal discrimination that had been piled on top of state discrimination,” including getting DOMA struck down by the Supreme Court as unconstitutional — which it was, in 2013, by a 5-4 ruling, in United States v. Windsor, paving the way for the 2015 decision that the U.S. Constitution guarantees the right to same-sex marriage.

On Wednesday, in response to the latest Gallup poll numbers, Wolfson tweeted that the strategy is “the gift that keeps on giving.”

“Part of reason I said [that] is the assets and allies and progress we brought in through marriage victory are now there for the next fight and the next fight — to protect trans people, to win employment protections … all beyond marriage, though the marriage lift continues to help all those causes,” he says. “We can take the power of what we gained and harness it to the next fight and the next fight.”

And the latest approval ratings, a benefit of that harnessed power, he says, have kept rising solely because of the passage of time with marriage equality — and the world not coming to an end. “One of the big claims we had to deal with again and again is that securing marriage equality would bring all these harms and disasters,” Wolfson says. “But instead, public support has grown — and broadened — and that’s because people are seeing with their own eyes: families helped, no one hurt.”

Read more from Yahoo Life:

• Dyllón Burnside of 'Pose' on being queer: 'News flash! I sleep with who I want'

• Tan France and confidence and becoming a dad: 'I've had to wait a very long time to make this happen'

• The Teletubbies embrace Pride, more than two decades after 'gay' Tinky Winky scandal

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