If the Supreme Court invalidates federal health insurance subsidies for individuals living in up to 37 states, Republicans would be open to a variety of policy responses to keep financial assistance flowing to those already enrolled in President Obama’s healthcare law.

But conversations with Republican lawmakers and aides in both the House and Senate indicate there is one red line that the GOP won’t be willing to cross. Simply put: A GOP Congress will never permanently extend the subsidies that were just declared illegal so that new enrollees could claim Obamacare benefits.