One U.S. senator is looking to bring up a vote on protecting churches from attempts to police their beliefs, after a presidential candidate said churches should lose their tax-exempt status if they oppose same-sex marriage.

Sen. Ben Sasse (R-Neb.) has introduced a resolution in the Senate expressing support for freedom of conscience (S.J.Res. 58). He said on Wednesday that his measure aims to put senators on the record on protecting the tax-exempt status of houses of worship, amidst attempts to condition that status on a church's support for same-sex marriage.

Introduced Wednesday, the joint resolution recognizes the importance of religious freedom to the framers of the Constitution and the role of religion in the history of the U.S., and says that the government cannot condition religious protections such as tax-exempt status upon certain viewpoints it deems "correct."

The resolution states that "government should not be in the business of dictating what 'correct' religious beliefs are; and any effort by the government to condition the receipt of the protections of the Constitution of the United States and the laws of the United States, including an exemption from taxation, on the public policy positions of an organization is an affront to the spirit and letter of the First Amendment to the Constitution of the United States."

Sasse introduced his resolution on Wednesday in response to comments by Democratic presidential candidate and former congressman Robert Francis "Beto" O'Rourke at a "#PowerOfOurPride" town hall on LGBTQ issues sponsored by the Human Rights Campaign and broadcast by CNN on Oct. 10.

At the town hall event, O'Rourke had said in response to a question by moderator Don Lemon that "religious institutions like colleges, churches, charities" should be stripped of their tax-exempt status if they oppose same-sex marriage.

O'Rourke's campaign later offered a clarification, saying he was not referring to the tax-exempt status of houses of worship but rather access to public grants and tax dollars of religious-based charities.

On Sunday, O'Rourke told MSNBC, "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."

Despite the clarification, however, the comments sparked backlash and questions about the constitutionality of such a proposal.

Sasse, on Wednesday, issued a rebuke of O'Rourke's original proposal on the Senate Floor, calling them "extreme intolerance," "extreme bigotry," and "profoundly un-American."

"I don't care what some nitwit said on CNN last week to satisfy his fringy base and try to get a sound bite in a presidential debate. The American people ought to know that this body stands for the historic First Amendment, that's what we all took an oath to uphold and to defend and that's what we ought to vote to affirm again," Sasse said.

The government cannot regulate the speech of churches and cannot "define true and false religion," he said.

"Government doesn't rifle through your pastor's or your rabbi's sermon notes, government doesn't tell your clerics what they can or can't say, government doesn't tell your religious leaders how they will perform their services, government doesn't tell you where or when you will worship," Sasse said.

The Supreme Court ruled in a 1970 decision Walz v. Tax Commission of the City of New York that tax exemptions for houses of worship did not violate the Establishment Clause of the First Amendment.

In a 7-1 decision, the Court said that such exemptions did not single out one particular religious group for favor, but rather "creates only a minimal and remote involvement between church and state, far less than taxation of churches would entail." Furthermore, two centuries of tax exemptions for churches "has not led to an established church or religion, and, on the contrary, has helped to guarantee the free exercise of all forms of religious belief," the Court said.

Other presidential candidates-Sen. Elizabeth Warren (D-Mass.) and Pete Buttigieg-said in the past week that they would not take such action to strip churches of tax exemptions.

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"Religious institutions in America have long been free to determine their own beliefs and practices, and she [Warren] does not think we should require them to conduct same-sex marriages in order to maintain their tax exempt status," a statement from the Warren campaign to NBC News read.

On CNN on Sunday, former South Bend, Indiana Mayor and Democratic presidential candidate Pete Buttigieg said that removing tax exemptions "means going to war not only with churches, but I would think with mosques and a lot of organizations that may not have the same view of various religious principles that I do."

He added that "if we want to talk about anti-discrimination law for a school or an organization, absolutely. They should not be able to discriminate."

At the same town hall where O'Rourke made his original comments, fellow presidential candidate Sen. Cory Booker (D-NJ), was also asked if he would strip houses of worship of tax-exempt status for opposing same-sex marriage, and responded that such a move would produce a "long legal battle," but added that "if you are using your position to try to discriminate others, there must be consequences to that. And I will make sure to hold them accountable using the DOJ or whatever investigatory [body]."