Updated

Missouri voters approved an amendment to the state constitution Tuesday that proponents say will help ensure the right to pray in public.

The amendment was on a statewide ballot and had widespread support, though critics said the right to pray is already protected under the U.S. Constitution and Bill of Rights.

State GOP Rep. Mike McGhee and other supporters agreed, but they said Amendment 2 is really an effort to make the state constitution match the U.S. Constitution and protect Christianity, which they said is under attack.

McGhee, whose legislation led to the amendment proposal, told FoxNews.com about an incident in which a teacher told a kindergartner singing “Jesus Loves Me” while swinging on the playground to instead sing “mommy loves me.”

McGhee thinks the teacher simply didn’t know the law and said the proposed amendment attempts to make clear such rights.

But critics said the amendment will open the door to more lawsuits.

Democratic State Rep. Chris Kelly told the St. Louis Post-Dispatch the proposed amendment was “a jobs bill for lawyers."

Critics dismissed the argument about rising hostility toward Christianity. They argued an amendment that reaffirms “the right to pray in a private or public setting" might lead to the exclusion of prayer from Muslim or Jewish religions, for example, which could triggers some of the likely suits.

Regardless, observers say the outcome of the vote likely will be challenged in federal court.

Another part of the amendment sparking controversy is a section that reads "no student shall be compelled to perform or participate in academic assignments or educational presentations that violate his or her religious beliefs."

Critics say schools will be forced to make perhaps an endless number of decisions on which assignments violate beliefs.

McGhee confirmed the section is rooted in a 2006 case, in which a Christian student at Missouri State University was asked as part of a class project to write and sign a letter to the Missouri legislature in support of gay adoption.

McGhee, whose District 122 is southeast of Kansas City, pointed out the 2006 case was quickly settled out of court, and he didn't foresee the amendment resulting in cases of “It’s against my religion to do algebra.”

He also hoped the amendment will prompt other states to take up similar measures.