“They don’t acknowledge the number of people who were hurt,” Mr. Edelman said. “It’s just not in their lens. It was predictably bad public policy.”

Image The measure weakened the friendship of Hillary Rodham Clinton and Marian Wright Edelman, shown in 1999. Credit... Todd Rosenberg

Forcing families to rely on work instead of government money went well from 1996 to 2000, when the economy was booming and paychecks were plentiful, economists say. Since then, however, job creation has slowed and poverty has risen. The current downturn could be the first serious test of how well the changes brought about by the 1996 law hold up under sharp economic stress.

“We should have enormous concern about the lack of a fully functioning safety net for families with children,” said Mark H. Greenberg, director of the Poverty and Prosperity Program at the Center for American Progress, a liberal research group.

In many ways, Mrs. Clinton has sought to moderate her liberal image since leaving the White House. But on welfare, she has faced the opposite problem: accusations from some liberals that she sold out their principles for a politically calculated centrism.

On the campaign trail, Mrs. Clinton is largely focused on the middle class. Since the departure from the Democratic race of John Edwards, who had made poverty a centerpiece of his campaign, there has been little debate about social welfare policy. But in promising on Friday to establish a cabinet-rank poverty-fighting position if she is elected, Mrs. Clinton reintroduced the topic and the question of her record.

In the interview, conducted last month, Mrs. Clinton said she had followed through on her promise to address what she viewed as shortcomings in the welfare law after being elected to the Senate in 2000. She said she had pressed for legislation that would have increased financing for child care for poor mothers by up to $11 billion, seeking to expand food stamps, and allowing welfare recipients to draw cash aid while attending school.

Those provisions were blocked by the Republican leadership.

“We’ve had to mostly spend our time since President Bush came in to office preventing bad things from happening,” Mrs. Clinton said.