“We hope to effectively repeal Obamacare,” he said, “which will then give President Trump and Congress an opportunity to replace that failed experiment with a plan that ensures Texans and all Americans have better choices for health coverage at more affordable prices.” (The suit argues that when the Republican tax law eliminated penalties for violating the A.C.A.’s individual mandate to buy insurance, it ended the constitutional rationale by which the Supreme Court had approved the law — that it was based on Congress’s right to tax.)

Among the Republican signatories to the lawsuit: Josh Hawley, the Missouri attorney general who challenged Claire McCaskill for her Senate seat while promising voters to protect coverage for pre-existing conditions; Republican officials from Wisconsin, where Gov. Scott Walker ran for re-election, and Georgia, where Secretary of State Brian Kemp ran for governor, making similar vows; and Pam Bondi, the Florida attorney general and close ally of Gov. Rick Scott, another Senate hopeful running ads saying pre-existing conditions should be covered.

Filing a request in April for a preliminary injunction — as in, “This is an emergency, please rule as soon as possible” — the plaintiffs were in a hurry to get the job done when they asked Judge O’Connor to blow up Obamacare. They admonished him in their filing that “the sooner an order issues enjoining the A.C.A., the better, both so that all states and individuals can prepare to operate and live without the A.C.A.”

This is not the first time opponents of Obama-era policies have asked Judge O’Connor to do their bidding. In 2016, they did it twice — first with a lawsuit challenging the legality of federal school guidance for accommodating transgender students and later with a suit calling for the invalidation of regulations applying the Affordable Care Act’s various anti-discrimination provisions. Judge O’Connor agreed that both of those cases required swift judicial intervention: After hearing oral arguments in each, he took nine and 11 days, respectively, to issue nationwide orders prohibiting the Obama administration from taking any further action that might cause what the law calls “irreparable harm” to the plaintiffs.

Judge O’Connor has expressed no urgency this time, on an issue that was central to the midterm campaigns.