While the Senate may in most cases have the power to “gut and amend” a bill by striking and replacing its entire contents, no court has ever held that the Senate can use such a procedure to originate a bill for raising revenue, he said.

“If Congress can use its taxing power to accomplish these goals, like forcing people to buy insurance, …that’s all the more reason why we need more democratic control over the taxing power,” Sandefur said. “This is the reason why the House of Representatives has this power in the first place.”

Interest in the case is growing despite its dismissal last June. Forty House Republicans filed an amicus brief in support of the challenge, while the House Judiciary Committee held a hearing recently on the meaning of the Origination Clause.

Two of the judges on the panel were recently appointed by President Obama and confirmed by the Senate as part of the so-called “nuclear option.” President Clinton appointed the other judge.

Whatever decision is reached, the supporters of the lawsuit intend to push it all the way to the Supreme Court.

“It’s always a long shot when you sue the federal government, particularly over the Affordable Care Act,” Sandefur said. “But we bring these cases because we believe in their constitutional merit.”