“President Obama will discuss the twin challenges of growing income inequality and shrinking economic mobility and how they pose a fundamental threat to the American dream,” the White House said in a statement.

He will describe “the steps he has taken to help reverse these trends, restore mobility and increase economic security for every American, including the economic benefits of the Affordable Care Act,” the statement said.

After being on the defensive for weeks about the health care program’s malfunctioning website and his own faulty promises, Mr. Obama previewed his economic case for the Affordable Care Act on Tuesday in a White House appearance with 19 people identified as its beneficiaries.

“For too long, few things left working families more vulnerable to the anxieties and insecurities of today’s economy than a broken health care system,” he said. “So we took up the fight because we believe that, in America, nobody should have to worry about going broke just because somebody in their family or they get sick.”