The Republican-controlled Texas House is poised to hear rules allowing religious child welfare agencies to block gays and same-sex couples from adopting children.
The measure protects agencies that object to such adoptions on religious grounds from being sued.
Social conservatives are championing it, but Democrats want to block it via stall tactics.
The prohibition should come via an amendment to a bill reorganizing the Department of Family and Protective Services, up for consideration Tuesday.
It has the votes to pass, but the amendment is attached to a Senate bill. That means it must clear the House by midnight, with the legislative session ending June 1.
That gives House Democrats a chance to run out the clock.
Adding to the tension is a potential last-minute vote on insurance coverage for abortion.
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