Racing both a U.S. Supreme Court decision on gay marriage and legislative deadlines, Texas Republicans pushed ahead Tuesday toward putting the state at the forefront of resistance if same-sex weddings are ruled constitutional.

Nearly every Republican in the Texas House is backing a measure that would prohibit state and local officials from issuing marriage licenses to same-sex couples. Less than three weeks remain in Republican Gov. Greg Abbott’s first session, and the bill must clear the House by midnight Thursday to advance.

If signed by Abbott, the bill would aim to defy the Supreme Court if it legalizes gay marriage, laying the groundwork for Texas to potentially raise new legal battles over its ability to regulate marriage licenses.

“It would certainly put the state in a position to challenge,” said Republican state Rep. Cecil Bell, who filed the bill shortly after a Texas judge allowed a lesbian couple to wed despite a statewide ban on gay marriage.

The measure would prohibit state and local officials from using taxpayer dollars “to issue, enforce, or recognize a marriage license … for a union other than a union between one man and one woman.”

Bell, from the outskirts of Houston, said the bill “simply preserves state sovereignty over marriage.”

The Alabama Supreme Court earlier this year already prohibited county officials in that state from issuing marriage licenses to same-sex couples. Lawmakers in South Carolina are also pushing a bill similar to what was filed in Texas, according to the Human Rights Campaign, which tracks gay rights issues.

Abbott didn’t give hot-button social issues legislative priority after taking office in January.

But with the Texas Legislature now close to adjourning, Republicans have accelerated legislation that gay rights activists consider hostile. This week began with the Senate giving approval for clergy members to refuse to perform marriages that violate their religious beliefs.

That bill was filed on the same day last month that the Supreme Court heard arguments in the landmark gay marriage case — and long after a Senate deadline for new legislation.

It’s not as divisive as religious objection measures in Indiana and Arkansas that set off intense blowback earlier this year. Texas gay rights activists say they can live with the clergy bill – which they consider redundant — but the restrictions over marriage license have them on edge.

Foes: ‘It’s shocking’

“It’s shocking that Texas lawmakers are pursuing a path that would set up this showdown,” said Rebecca Robertson, the legal and policy director for the ACLU of Texas.

That Bell’s bill already has so much support in the Texas House — which is more moderate, at least by the standards of Texas politics — signals that the Senate would also favorably greet the measure. The session ends June 1.

Some legal experts question the success Texas would have raising challenges over state sovereignty, saying those arguments have already been made to the Supreme Court in the current case.

“Any kind of appeal or challenge the state would bring would bring a fairly summary rejection by the Supreme Court,” said Carl Tobias, a law professor at the University of Richmond. “I don’t know what purpose it serves.”

Gay marriage is now legal in 37 states and the District, and support for it is rising. Nationally, a record 6 in 10 people said they supported same-sex marriage in a Washington Post-ABC News poll conducted last month.

Even in Texas, opposition to gay marriage is dwindling. Polling conducted by the Public Religion Research Institute in 2014 shows that nearly half of Texans, 48 percent, support same-sex marriage, and 43 percent oppose it.

Backlash brewing

In a teleconference with reporters, critics of the Texas measure predicted that it would provoke a backlash like those that roiled Indiana and Arkansas this year, after those states attempted to enact religious protections that were viewed as anti-gay. They fear that a victory in Texas could prod other states to copy the approach.

That could lead to a standoff much like the conflict that arose in the 1950s over school desegregation, gay rights advocates said. That battle eventually ended in the capitulation of resistant Southern states – but only after years of litigation slowed the advance of civil rights.

“Texas is pioneering a new strategy to prevent equality for its LGBT residents, to ignore the U.S. Supreme Court and even roll back gains that have been made in the state,” said Chuck Smith, president of Equality Texas, a gay rights group.

The debate also comes on the heels of action Tuesday in the Texas Senate giving final approval the so-called Pastor Protection Act, which would ensure that clergy members have the right to refuse to marry same-sex couples.

The House has yet to act on that legislation.

Staff writer John Gravois contributed to this report, which includes material from The Washington Post.