The Senate is set to move Wednesday toward enshrining marriage equality into federal law, a historic moment that elected leaders across the political spectrum say represents a milestone for Congress and the nation.

“Just a few years ago, there would not be the support there is today for protecting the marriages of people in interracial and same-sex marriages,” Sen. Tammy Baldwin (D-Wis.), who led the charge to pass the Respect for Marriage Act in the Senate, said Tuesday, ahead of Wednesday’s first procedural vote on the measure. 

Baldwin, who in 2012 became the first openly gay person elected to the upper chamber, said the Supreme Court’s 2015 ruling in Obergefell v. Hodges, which legalized same-sex marriage nationwide, has been instrumental in changing the “hearts and minds” of those previously opposed to gay unions.

“Everybody knows couples that want nothing more than to make sure their families are protected like everyone else,” she told The Hill. “It’s heartening to see the progress.” 

The Respect for Marriage Act, a version of which was passed by the House in July, seeks to address a national patchwork of marriage laws by requiring states to recognize interracial and same-sex marriages as legally valid if those ceremonies were performed in one of the 15 states without a constitutional amendment or statute that prohibits them. 

It would also officially repeal the Defense of Marriage Act (DOMA), the 1996 law defining marriage as a union between one man and one woman. Both DOMA and individual state laws refusing to recognize same-sex marriages are unenforceable under protections established by the Obergefell ruling. 

But the protections of Obergefell received a warning shot this summer from Justice Clarence Thomas, who, in a concurring opinion when the Supreme Court overturned the federal right to an abortion, said the rights to marriage equality and contraception should also be reconsidered by the high court. Thomas’s opinion set off alarm bells, spurring the Democratic-controlled House to act on the Respect for Marriage Act. 

Senate Democrats had eyed a vote on the House-passed measure in September but agreed to delay until after the midterms when Republicans indicated it would increase the likelihood of it getting enough GOP support to overcome a filibuster. 

“If I wanted to pass that and I was the majority leader and I wanted to get as many votes as I could possibly get, I’d wait until after the election to have the vote,” retiring Sen. Roy Blunt (R-Mo.) said at the time.   

Support for marriage equality among American voters hit an all-time high in June, and nearly 60 percent of adults in a July Politico and Morning Consult poll said the right to same-sex marriage should be shielded by federal legislation, including more than a third of Republicans and three-quarters of Democrats surveyed. 

Even the Church of Jesus Christ of Latter-day Saints, which in 2008 spent millions of dollars to support California’s Proposition 8, which effectively banned gay marriage in the state, came out in support of the Respect for Marriage Act on Tuesday.

“It’s incredibly important to me as an LGBTQ American, as someone who’s coming into Congress, to know that I have colleagues who are fighting on behalf of my rights,” said incoming Rep. Becca Balint (D), who in last week’s midterm elections became the first openly LGBTQ person and first woman sent to Congress from Vermont. 

Balint told The Hill on Tuesday she doesn’t believe recent additions to the bill that bolster religious liberty protections are necessary, but “if that is what we need to do right now, I want to make progress.”

“I would always rather get half of a loaf than no loaf,” she said. 

Just four Senate Republicans — Mitt Romney (Utah), Rob Portman (Ohio), Thom Tillis (N.C.) and Susan Collins (Maine) — have backed the Respect for Marriage Act publicly, but senators including Baldwin and Portman have suggested the measure has enough bipartisan support to overcome a filibuster. 

“It gives families all over America the peace of mind to know that their marriages are going to be valid in other states,” Portman, who is retiring after this Congress and whose conservative views on same-sex marriage shifted after his son, Will, came out as gay in 2011, told The Hill Tuesday. “I think that’s an important thing for us to assure people about.” 

If the updated bill does advance through the Senate, it will return to the House for a vote.

Senate Majority Leader Charles Schumer (D-N.Y.) on Monday took procedural steps that set the groundwork for an initial Senate vote on the bill, which is slated for Wednesday. 

“No American should ever, ever be discriminated against because of whom they love, and passing this bill would secure these much-needed safeguards into federal law,” Schumer said Monday. 

Still, lawmakers agree that the bill isn’t a perfect solution and falls short of preventing the Supreme Court from overturning Obergefell and curtailing the rights of same-sex couples. 

“It’s a workaround and it provides some stability and security for same-sex unions,” Rep. Mark Takano (D-Calif.), who voted in favor of the measure in the House, told The Hill Tuesday. “But the problem of extreme arrogance in the Supreme Court remains.” 

“We have to do this because we’re worried about this — this is not a great thing,” Takano, one of nine openly gay House members, said Tuesday. “But it’s a happy day if the Senate moves on this.” 

Aris Folley contributed. Updated at 10:13 a.m.