At Last, Democrats Get Chance to Engineer Obamacare 2.0

“Any one of these changes individually is moderate, but stack one on top of another and you get a big boost to the Affordable Care Act,” said Jonathan Cohn, author of “The Ten Year War,” a new history of the health law. “It doesn’t change the law’s structure, but it does make it much more generous.”

Those close to the effort say its ambitions — and its limits — reflect the preferences of those leading the way. Mr. Biden, who was involved in the passage and rollout of Obamacare as vice president, ran on the idea of expansion, not upheaval. And leaders in Congress who wrote Obamacare have been watching it in the wild for a decade, slowly developing legislation to address what they see as its gaps and shortcomings. Many see their work as a continuing, gradual process, in which lawmakers should make adjustments, assess their effects, and adjust again.

“When you think about where we thought the A.C.A. was headed four years ago, and contrast that to where we are right now, on the cusp of a massive expansion of affordability, it’s pretty exciting,” said Christen Linke Young, deputy director of the White House Domestic Policy Council for Health and Veterans Affairs.

But Bob Kocher, an economic adviser in the Obama administration who is now a partner at the venture capital firm Venrock, said that beyond the current changes, Mr. Biden’s mission on Obamacare seemed more modest, more like “don’t break it.”

“I don’t think he has any ambition in mind beyond managing it,” he said.

To aid in the effort, President Biden has recruited a host of former Obama administration aides. His picks for top jobs at the Centers for Medicare and Medicaid Services, the Office of Management and Budget, as well as key deputies at H.H.S., all worked on the first rounds of Obamacare policymaking. Many key congressional aides working on health care now also helped write the Affordable Care Act.

Born in the Great Recession, the Affordable Care Act was drafted with a focus on costs. Political compromises and concerns about runaway deficits kept the law’s overall 10-year price tag under $1 trillion, and included enough spending cuts and tax increases to pay for it. Those constraints led its architects to scale back the financial help for Americans buying their own coverage. Staffers who wrote the formulas said they ran hundreds of simulations to figure out how to cover the most people within their budget.

Those who wrote the regulations that interpreted the law also recall drafting rules that erred on the side of spending less to avoid blowback or litigation.