Democratic presidential hopefuls Sen. Elizabeth Warren, D-Mass., and Mayor Pete Buttigieg of South Bend, Indiana, rejected a threat by fellow 2020 hopeful Beto O’Rourke to strip the tax-exempt status of churches that oppose same-sex marriage.

O’Rourke’s proposal, first made Thursday evening at a presidential forum on LGBTQ issues, has spawned a backlash against the former Texas congressman, though O'Rourke and his campaign have since backtracked on the initial remarks.

“Do you think religious institutions like colleges, churches, charities should lose their tax-exempt status if they oppose same-sex marriage?” CNN’s Don Lemon asked O’Rourke at Thursday’s forum.

“There can be no reward, no benefit, no tax break for anyone, or any institution, any organization in America, that denies the full human rights and the full civil rights of every single one of us,” O’Rourke responded to applause. “And so as president, we are going to make that a priority, and we are going to stop those who are infringing upon the human rights of our fellow Americans.”

O’Rourke appeared to go further than the existing political and legal conversation over LGBTQ rights and religious discrimination, which has centered on questions about private businesses declining services and refusing to hire or maintain LGBTQ employees.

O’Rourke and his campaign staff, however, appeared to walk back his initial comments. On Friday, his spokeswoman, Aleigha Cavalier, suggested the candidate’s remarks had been misinterpreted.

“Of course, Beto was referring to religious institutions who take discriminatory action," Cavalier said. "The extreme right is distorting this for their own agenda.” She added that O'Rourke defined discriminatory action as "denying public accommodation" on the basis of gender, sexuality or marriage.

Then on MSNBC’s “Kacie DC” on Sunday, O’Rourke sought to clarify his stance.

“The way that you practice your religion or your faith within that mosque or that temple or synagogue or church, that is your business, and not the government's business,” he said. “But when you are providing services in the public sphere, say, higher education, or health care, or adoption services, and you discriminate or deny equal treatment under the law based on someone's skin color or ethnicity or gender or sexual orientation, then we have a problem.”

During an appearance on CNN’s “State of the Union” on Sunday, Buttigieg, the only openly gay candidate in the 2020 field, rejected O’Rourke’s tax threat. While Buttigieg emphasized the importance of anti-discriminatory policies in many institutions, including schools, he drew the line before O’Rourke’s more controversial take on tax-exemption.

“The idea that you’re going to strip churches of their tax-exempt status if they haven’t found their way toward blessing same-sex marriage — I’m not sure he understood the implications of what he was saying,” Buttigieg said of O’Rourke.

Withholding tax-exempt status from religious organizations, according to Buttigieg, could dishonor the separation of church and state outlined in the First Amendment.

“That means going to war with not only churches but also mosques and organizations that don’t have the same view of religious principles as I do,” he continued. “Going after the tax exemption of churches, Islamic centers or other religious facilities in this country is just going to deepen the divisions we’re already experiencing.”

Elizabeth Warren also rejected O’Rourke’s tax threat. In a statement sent to NBC News on Monday, the Warren campaign’s deputy press secretary, Saloni Sharma, made clear she and O’Rourke are not aligned on the issue.

"Elizabeth will stand shoulder to shoulder with the LGBTQ+ community until every person is empowered and able to live their life without fear of discrimination and violence,” Sharma stated. “Religious institutions in America have long been free to determine their own beliefs and practices, and she does not think we should require them to conduct same-sex marriages in order to maintain their tax exempt status."

Prior to O’Rourke’s 2020 primary opponents chiming in, the Texas Democrat’s comments had already sparked condemnation from prominent Republicans and conservatives. Even President Donald Trump sought to capitalize on O’Rourke’s remarks.

Speaking on Saturday at the Values Voter Summit, Trump, without using O’Rourke’s name, told religious conservatives that he “will never allow the IRS to be used as a political weapon.”

“As you know, just a few days ago, a Democrat running for president proposed revoking the tax-exempt status of many churches and religious groups,” Trump said at the annual event. “And you know why it is. He’s a wacko.”

Hours after Trump’s remarks, O’Rourke fired back on Twitter.

"This from a man who’s used his office to stoke hate, fear, and discrimination. Who tried to ban Muslims," O'Rourke wrote. "Anyone can believe what they want — but organizations that discriminate when they provide public services should not be tax-exempt.”

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