Sen. Susan Collins, R-Maine, listens during a Senate Intelligence Committee hearing on the nomination of William Burns to be director of the Central Intelligence Agency (CIA) on Capitol Hill in Washington, U.S., February 24, 2021. Credit: AP / AP

U.S. Sen. Susan Collins is no longer co-sponsoring the Equality Act, a blow to advocates hoping to build bipartisan support for a landmark bill which would bar discrimination on the basis of sexual orientation or gender identity across the country.

The Maine Republican — who was the only member of her party to co-sponsor a similar version of the bill in 2019 and signed a letter with several Democratic senators last summer urging then-Senate Majority Leader Mitch McConnell, R-Kentucky, to bring it up for a vote — cited the need for unspecified changes and said she may introduce her own bill.

The Equality Act, which has been introduced in various versions since the 1970s, would amend federal civil rights laws to bar discrimination on the basis of sexual orientation or gender identity in a range of areas, including employment, housing, jury selections and programs that receive federal funding. Maine is one of 22 states that already prohibits discrimination in those ways, according to the LGBTQ-rights Movement Advancement Project.

Collins spokesperson Annie Clark said Wednesday that the Maine senator agreed to introduce the bill with an “agreement that all of the cosponsors would work together to make further changes” but that others “were unwilling to work out those changes.” She declined to specify the changes Collins was pushing for, however.

“Senator Collins supports ensuring fairness and equal treatment of all Americans, regardless of their sexual orientation or gender identity, and she is considering all possible options to do so, including introducing her own bill,” Clark said.

Collins has bucked her party in backing LGBTQ rights in high-profile votes throughout her career. She opposed two federal efforts to ban same-sex marriage in the 2000s and was one of eight Republican senators to vote to overturn the military’s “Don’t Ask, Don’t Tell” policy in 2010.

She announced her support for gay marriage in 2014, two years after Maine legalized it but before it was legal nationwide, and was endorsed that year by the Human Rights Campaign, a prominent LGBTQ-rights advocacy group that has lobbied heavily for the Equality Act.

But the group backed her Democratic challenger, House Speaker Sara Gideon, in 2020, citing Collins’ vote to confirm Supreme Court Justice Brett Kavanaugh and the need for a Democratic majority in the U.S. Senate. It slammed her a few months later for accepting an endorsement from the evangelical Christian Civic League of Maine, which led the fight against same-sex marriage in Maine when it passed at referendum in 2012.

In a Wednesday statement, David Stacy, government affairs director for the Human Rights Campaign, characterized Collins as a “strong advocate” for legislation to protect LGBT people from discrimination, adding that “her leadership is critical” on the issue.

Collins was re-elected decisively last year while Democrats gained control of the 50-50 Senate after Joe Biden won the presidency. He has identified the Equality Act as one of his priorities for his first 100 days in office and it is expected to easily pass the House this week.

But 10 Republican votes will still be necessary to overcome the filibuster in the Senate and it will be a challenge for Democrats. Republicans opposing the bill have generally argued that the anti-discrimination provisions would infringe on religious freedom and, more recently, raised the issue of transgender children’s participation in sports.