In the summer of 1996, President Bill Clinton delivered on his pledge to “end welfare as we know it.” Despite howls of protest from some liberals, he signed into law a bill forcing recipients to work and imposing a five-year limit on cash assistance.

As first lady, Hillary Rodham Clinton supported her husband’s decision, drawing the wrath of old friends from her days as an advocate for poor children. Some accused the Clintons of throwing vulnerable families to the winds in pursuit of centrist votes as Mr. Clinton headed into the final stages of his re-election campaign.

Despite the criticism and anxiety from the left, the legislation came to be viewed as one of Mr. Clinton’s signature achievements. It won broad bipartisan praise, with some Democrats relieved that it took a politically difficult issue off the table for them, and many liberals came to accept if not embrace it.

Mrs. Clinton’s opponent in the race for the Democratic presidential nomination, Senator Barack Obama, said in an interview that the welfare overhaul had been greatly beneficial in eliminating a divisive force in American politics.