Senator Mike Lee, a Republican from Utah, has introduced a bill which seeks a religious exemption for opponents of gay marriage.

“It is concerning that we have people in this administration who think that religious liberties are just not that big of a deal,” Lee told the Washington Examiner.

Lee's legislation is a companion piece to a House bill introduced in September by Idaho Rep. Raul Labrador. The House version of the Marriage and Religious Freedom Act has attracted 91 co-sponsors as of Wednesday, December 11.

According to the Examiner, six Republican senators have signed on to Lee's bill: Senator Marco Rubio of Florida, Orrin Hatch of Utah, Tom Coburn of Oklahoma, David Vitter of Louisiana, Pat Roberts of Kansas and Jim Inhofe of Oklahoma.

“Religious freedom … is under attack by the current administration,” Vitter said. “This bill will protect groups from administrative attacks, such as additional hurdles with taxes or obtaining federal grants or contracts.”

Freedom to Marry President Evan Wolfson has previously condemned the House version of the bill as a “Trojan House” which “would swallow civil rights laws and subvert constitutional protections.”

“Decades of civil rights struggle, and long experience with both federal and state non-discrimination statutes, have made clear that we don't need to gut non-discrimination laws to protect true religious freedom, and neither private religious views nor prejudice should get a special license to discriminate in the public sphere,” Wolfson said.