Hillary Clinton on Tuesday nabbed the endorsement of the Human Rights Campaign (HRC), the nation’s largest LGBT rights organization, edging out her two Democratic primary rivals who also boast strong records on equality.

“Out on the campaign trail, we’ve seen Secretary Clinton fight back against Republicans threatening to block our progress – and revoke, repeal and overturn the gains made during President Obama’s two terms. Just as she has fought for lesbian, gay, bisexual and transgender (LGBT) people as first lady, U.S. senator and secretary of state,” HRC said in an email blast that also included a link to Clinton’s record and agenda on LGBT equality. Clinton will join HRC members and supporters in Iowa next week to accept the group’s official endorsement.

In a statement, Clinton said she was “honored” to receive HRC’s support, adding that “our work is far from over.”

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“Too many LGBT Americans still face discrimination—in employment, in housing, in education, in health care—because of who they are or who they love,” Clinton said. “And the stakes in this election couldn’t be higher. The Republican candidates for president have not only hurled hateful, insulting rhetoric about the LGBT community—they’ve made it clear that if elected, they will roll back the rights that so many have fought for.” view photo essay Political Theatre: The presidential campaign of Hillary Clinton Clinton arguably boasts experience in government unparalleled by anyone in the presidential field — but that has also made her a high-profile target for attack.

Among her campaign promises, Clinton vowed to fight for passing the Equality Act, a bill that would bar LGBT discrimination nationwide in employment, housing and public accommodations; eliminating the military’s ban on transgender service members; and ending “conversion therapy” among minors, a medically discredited practice that seeks to turn gay people straight.

“I’m proud to stand with the Human Rights Campaign in this fight,” Clinton said. “Together, we can and will make our country—and our world—more just, fair and equal for generations to come.”

HRC’s endorsement comes as no surprise. A staunch LGBT rights advocate, Clinton celebrated the Supreme Court’s decision last June to make marriage equality the law of the land. As secretary of state, she prioritized the elimination of violence and discrimination against LGBT people, famously declaring in a 2011 speech in Geneva that “gay rights are human rights.” And as a senator, Clinton repeatedly co-sponsored the Employment Non-Discrimination Act (ENDA), which at the time would have barred discrimination against employees on the basis of sexual orientation. (A later version of ENDA also banned employment discrimination on basis of gender identity; it has never cleared Congress.)

“I see the injustices and the dangers that you and your families still face,” Clinton said in an address to HRC last October. “And I’m running for president to end them once and for all.”

Despite these achievements, Clinton’s record on LGBT equality is not exactly a profile in courage. In the 2008 election, both Clinton and her chief rival, then-Sen. Barack Obama, said they were opposed to allowing gay and lesbian couples the right to wed. When Clinton announced she had “evolved” into a marriage equality supporter in 2013 – a year after Obama did – some criticized her for taking so long. Clinton did not say she believed the U.S. Constitution guaranteed same-sex couples the right to wed until April 2015, the same month that the Supreme Court heard oral argument in the landmark case of Obergefell v. Hodges, which ended up finding same-sex marriage bans unconstitutional.

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All this has made Clinton’s presidential campaign somewhat vulnerable to attacks from the left. So has the record of her husband, former President Bill Clinton, who signed into law two anti-gay measures: “don’t ask, don’t tell” (DADT), the military’s former ban on openly gay service members; and the Defense of Marriage Act (DOMA), which defined marriage as the union between one man and one woman at the federal level. Clinton also signed into law the Religious Freedom Restoration Act (RFRA), a measure that was intended to protect religious minorities from unnecessary government intrusion, but has in recent years inspired a wave of anti-LGBT legislation that would essentially sanction discrimination on religious grounds. Several Republican presidential candidates have vowed to protect “religious freedom” if elected, widely interpreted today to mean they would protect the right of business owners – or in some cases, government officials – to turn away gay and lesbian couples based on religious objections to same-sex marriage.

Clinton denounced Indiana’s controversial RFRA when it became law last year, but she has never addressed the question of whether these types of statutes misrepresent the federal version.

Both former Maryland Gov. Martin O’Malley and Vermont Sen. Bernie Sanders also have strong records on LGBT equality. In 2012, O’Malley signed into law a measure legalizing marriage equality, making Maryland the eighth state to allow gay and lesbian couples to wed. Sanders, meanwhile, has a long history of opposing anti-gay laws – including the ones enacted under the Clinton administration. He opposed DADT in 1993 and was one of just 67 members in the House of Representatives to vote against DOMA three years later. Sanders also supported civil unions in Vermont in 2000. He came out in favor of marriage equality in 2009.

“I’m not evolving when it comes to gay rights,” Sanders told the New York Times last year. “I was there.”