The Oklahoma House's 56-21 vote sent its measure to Republican Gov. Mary Fallin, who has not said whether she would sign it. It's similar to laws in at least five other states.
In Kansas, negotiators for the state House and Senate drafted a new version of a bill that would prevent the state from barring agencies from providing foster care or adoption services if they refuse to place children in homes violating their "sincerely held" religious beliefs. The Senate passed an earlier version in March, only to see it stall in the House.
Supporters of such measures argue that the core issue is protecting a group's right to live out its religious faith, while critics see them as attacks on LGBT rights.
In Kansas, supporters hoped both legislative chambers could vote on the new version of the bill Thursday, with the House going first. GOP Gov. Jeff Colyer's supports it, with his administration arguing that it would encourage faith-based groups to place more abused and neglected children in state custody.
Backers of the Kansas bill acknowledged that faith-based agencies have been operating in Kansas for decades without issue. But they fear that lawsuits or turnover among state officials could result in an environment hostile to some religious groups' views.
"This is a matter of activist groups who don't like certain religious beliefs and they want to use the power of the government to crush people that operate according to those religious beliefs," said Kansas Catholic Conference director Michael Schuttloffel said.
LGBT-rights advocates argue that enacting such a law would sanction discrimination and support it with taxpayer dollars. TechNet, representing some of the biggest names in tech, including Apple and Google, sent a letter to lawmakers in both states opposing their measures.
"This vampire just won't die," said Kansas state Sen. David Haley, a Kansas City Democrat.
The Oklahoma bill cleared the GOP-controlled Legislature over the boisterous objections of Democrats. At one point, the chamber's presiding officer threatened to have a member forcibly removed.
Texas, Alabama, South Dakota, Virginia and Michigan already have such laws in place. Michigan's ACLU chapter took the state to court last year over its adoption law, and the case is still ongoing.
In 2011, Illinois declined to renew its state contract with Catholic Charities adoption services due to its policy of refusing child placement to same-sex couples. Catholic Charities has also stopped handling adoptions in Washington D.C., Massachusetts and San Francisco over concerns they would be required to act against their religious beliefs.
In Kansas, both sides of the debate agree that the state's foster care system is overloaded. The number of kids in need of homes has grown every year since 2008, from 5,711 to 7,540 as of March, according to the Department of Children and Families.
Supporters said that passing the measure could encourage groups providing limited services for the state or doing only private adoptions to work more with the state. Colyer's administration has said some out-of-state agencies could be attracted to Kansas.
In Oklahoma, sponsoring state Sen. Greg Treat, an Oklahoma City Republican, said he believes his measure will help get more children into loving homes.
"I believe this bill aids and gets more people involved in the system," he said.
But critics like Lori Ross, president of Foster Adopt Connect, a child placement agency operating in Kansas and Missouri, contend the real problem is a lack of available families.
Ross said for LGBT families looking to adopt, it isn't always obvious which agencies will work with them and which won't, she said. If they make that first phone call and get denied, they may never try and adopt again.
"If you're a single person, or a gay person, or a divorced person, or you're Jewish, then you better think twice before you call," Ross said.
Also contributing to this report were Sean Murphy in Oklahoma City, and John Hanna in Topeka, Kansas.