WASHINGTON — Republican lawmakers who have spent two years railing against President Obama’s health care law are beginning to devise alternatives so they can be ready if the Supreme Court forces the issue of the uninsured back into the center of political debate.

“If Obamacare goes away, it doesn’t mean that the problem of how you deliver health care affordably and get good access goes away,” Representative Greg Walden, Republican of Oregon, said. “Those are the issues that are back before us.”

Republicans say they will have to make good on their pledge to replace the health care law if the Supreme Court strikes down any significant parts of it. They remain optimistic about the possibility of a court victory, even as they begin thinking more seriously about what would follow.

“Our wheels are beginning to turn,” said Representative Fred Upton, Republican of Michigan and chairman of the House Energy and Commerce Committee, which would have a large role in developing Republican alternatives to the Obama health care law.