AUSTIN, Texas — As "bathroom bills" targeting transgender individuals falter across the U.S., fizzling even in conservative bastions like Kansas and Arkansas following the upheaval over a North Carolina law last year, Texas Republicans are doubling down in their determination.

The resolve to make Texas only the second state to restrict bathroom access for transgender persons before Monday — when lawmakers adjourn until 2019 — is raising the possibility of a special session and exasperating business groups and LGBTQ rights organizations that have united in opposition for months.

Republican Gov. Greg Abbott said Thursday enough time remains for lawmakers to strike a deal. He said Texas must address student "privacy, safety and security" but didn't say how far a bill must go — including whether it must require transgender people to use bathrooms that correspond with the sex on their birth certificate.

In this May 4, 2017, photo Joanna Smith, of Houston, walks her twin first-graders home from school. One of her children is transgender and Smith fears the child's school would be compelled by the state to "out" her child's biological gender should a "bathroom bill" become law. John L. Mone / AP

Hours later, the state Senate rejected a version of LGBTQ restroom restrictions meant to apply only to public schools that the House passed last weekend, and asked for a conference committee. The Senate previously approved broader rules requiring all transgender Texans to use public restrooms corresponding to the genders on their birth certificates, and those differences will have to be reconciled.

But any version that emerges would make Texas the first state to pass a bill reminiscent of North Carolina's controversial 2016 law that was partially repealed in March following intense political and economic backlash.

More than a dozen states this year considered bills restricting bathroom access for transgender people, including Kansas, where the GOP-controlled House this week refused to debate a "bathroom bill" amendment proposed by a freshman legislator.

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Related: Texas Lieutenant Governor Threatens Special Session for Bathroom Bill

It was emblematic of what LGBTQ rights groups say has doomed most efforts outside Texas: a lack of buy-in from Republicans in charge.

"They tended to be introduced by folks who were more extreme members of the party, were less likely to get committee hearings, less likely to move. They were much less likely to be taken seriously," said Cathryn Oakley, senior legislative counsel for the Human Rights Campaign. "The big difference in Texas is, they have been taken seriously."

Related: Texas Governor Gives First Clear Support for ‘Bathroom Bill’

Abbott, a social conservative presiding over his last legislative session before he faces re-election in 2018, has gone against his Republican peers by calling for such a law. Governors in Arkansas and Kentucky have rebuffed the efforts as unnecessary, and South Dakota's Republican governor vetoed a proposal in March.

They watched as Republican Pat McCrory, who signed and defended the North Carolina bill as governor, became the only incumbent governor in the U.S. to lose in the general election last year.

But Abbott has become vocal in the final weeks of Texas' legislative session.

"We want to do all we can to help women have privacy, safety and security to the fullest extent possible," Abbott said Thursday.

Opponents have challenged Republicans on such assertions, calling them baseless and noting laws are already on the books when it comes to safety in bathrooms.

Lt. Governor Dan Patrick issued an ultimatum to the Texas House on Wednesday, May 17, saying he must see passage of two of his priorities -- property tax relief and limits on transgender-friendly bathroom policies -- before the Senate will act on key legislation to keep some state agencies operating. Deborah Cannon / AP

The determination for a Texas bill began with Republican Lt. Gov. Dan Patrick, who controls the Senate and led Donald Trump's presidential campaign in Texas.

Patrick is popular with conservative activists who drive Texas politics but has denied eyeing higher office in 2018, including speculation of challenging Abbott. Patrick has signaled willingness for a special session over a bathroom bill, although only Abbott can make that call.

The Senate's original bill was similar to North Carolina's and Patrick has rejected the House's weakened version, though compromise is still possible in conference committee.

"Frankly some of the other threats in other states rang pretty hollow in a state like Texas," Republican Sen. Larry Taylor said. "They make more off of us than we make off of them."

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