PHOENIX >> With little debate, Arizona last year became the only state to impose a one-year limit on cash assistance to needy families, cutting the maximum duration of benefits for the third time since 2010. The newest limit has begun to hit home for welfare recipients who are learning that their benefits are nearing an end.

Anna Robinson, the mother of a 4-year-old boy, received cash assistance for about eight months in 2013, until she landed a job at a call center for a pet-supply retailer. Then her job was automated and her position was eliminated. She will receive about four months of cash payments before they dry up.

“I was really proud of myself when I got a job, but now I need help again,” Robinson said as she picked up a box of free groceries at St. Mary’s Food Bank in West Phoenix.

As the 20th anniversary of Bill Clinton’s welfare law approaches, the impact of its requirements is being felt more than ever, with the political rifts that it exposed in 1996 resurfacing on the 2016 campaign trail.

In her 2003 autobiography, “Living History,” Hillary Clinton said she agreed with her husband’s decision to sign the welfare bill, even though it “outraged some of our most loyal supporters.” The old program of Aid to Families With Dependent Children, created in the New Deal, “helped to create generations of welfare-dependent Americans,” she wrote.

Her rival for the Democratic presidential nomination, Sen. Bernie Sanders of Vermont, fiercely opposed the law as a House member then and continues to press his case against it.

“I spoke out against so-called welfare reform because I thought it was scapegoating people who were helpless, people who were very, very vulnerable,” Sanders said at a campaign stop in February. “Secretary Clinton at that time had a very different position on welfare reform.”

Off the campaign trail, the real-world effects are coming into clearer focus. Arizona is perhaps the most vivid example of a national trend: the withering of the cash assistance program created by the law, known as Temporary Assistance for Needy Families.

Cash benefits in Arizona are smaller now than when Congress created the assistance program 20 years ago. In 2009, Arizona reduced the maximum benefit by 20 percent, to $278 a month for a family of three with no other income. That cut, coupled with inflation, has reduced the buying power of the maximum benefit by about half.

The federal law required states to set time limits on the receipt of cash assistance and specified that the payments could not exceed five years, which is still the limit in about two-thirds of the states.

In 2010, Arizona cut cash-assistance eligibility to three years, from five. In 2011, it reduced the limit to two years. Then last year it dropped to one, with that limit to begin on July 1.

“The 12-month time limit is rapidly approaching,” said Michael Wisehart, an assistant director at the Arizona Department of Economic Security, which runs the welfare program.

Any cash assistance received since October 2002 counts against the limit, according to state law and letters being sent to welfare recipients. That means even a few months spent on welfare a decade ago can significantly limit future benefits. Arizona officials estimate that 1,200 to 1,600 families — roughly 15 percent of those receiving cash assistance — will be affected. Some may qualify for hardship exemptions.

Domonique Christian, 27, recently received a notice from the state saying that her cash assistance payments of $220 a month might soon be terminated because she had exceeded the new 12-month limit on benefits.

Christian, a single mother, said she could not afford to lose the aid. She has two young sons and no job. That money, she said, is for diapers, clothing and food for her children, bus fare and other daily expenses.

“The money,” she said, “is really low, but it will get you by. It helps. It’s better than nothing.”

Here, as in several other states, proponents say the strict limits will create a new impetus for welfare recipients to find jobs and will reduce their reliance on public benefits. When President Clinton signed the welfare law in 1996, he said it would replace “a never-ending cycle of welfare” with “‘the dignity, the power and the ethic of work.”

And for a while, it did. Welfare cases fell sharply, employment of single mothers increased and harsh critics of the program acknowledged that the first years were not nearly so bad as they had predicted. Children were not sleeping on grates.

But the number of welfare recipients did not increase much even as the economy softened and poverty inched up in the recession that began in 2007.

“The high marks given to the 1996 reform at its 10-year anniversary are much lower now as we approach its 20-year anniversary,” said Sandra Danziger, an expert on poverty and social welfare policy at the University of Michigan.

Caseloads during the recession increased far less than the number of people receiving food stamps or unemployment insurance benefits. The cash assistance program generally requires people to work to get benefits, but work was not readily available.

“The program did not respond to economic need in the Great Recession,” said Hilary Hoynes, a professor of economics and public policy at the University of California, Berkeley.

Many Republicans, including House Speaker Paul Ryan of Wisconsin, still point to the welfare law as a success and a model for reinventing other domestic programs.

But for many Democrats, swept up more by Sanders’ liberal populism than Bill Clinton’s centrism, the law is far less popular. Clinton, defending his wife, says she argued against more extreme welfare proposals that would have capped federal spending on Medicaid and food stamps. Her campaign notes that child poverty decreased more than 25 percent in the Clinton years and says that many families benefited from expansion of the earned-income tax credit under President Clinton.

The welfare law has indisputably achieved one of the goals that Clinton announced in his first campaign for president, to “end welfare as we know it.”

Nationally, the number of people receiving cash assistance has fallen to 4.1 million, from 12.3 million in 1996. In Arizona, the number of cash assistance recipients has plummeted to 20,495, from a monthly average of 155,000 in 1996-97.

The 1996 law reversed six decades of social welfare policy, eliminating the individual entitlement to cash assistance for the nation’s poorest children and giving each state a lump sum of federal money with vast discretion over its use. The amount of the main federal block grant has remained at $16.5 billion annually since the law was adopted, but inflation has shrunk the value of that money about a third.

In addition, the reach of the program has been greatly reduced.

In 1996, for every 100 families in poverty, 68 received cash assistance. That fell to 23 for every 100 in 2014. And in a dozen states including Arizona, the number is fewer than 10 in 100.

In response, the very poor have devised what Kathryn Edin, a professor of sociology at Johns Hopkins University, called survival strategies. Some, she said, sell plasma, a blood component. Some collect metal junk and aluminum cans and sell them to scrap dealers. Some move in temporarily with friends or relatives to save on rent.

“We’ve shredded our cash safety net,” said Edin, who examined those tactics in her book “$2.00 a Day: Living on Almost Nothing in America.”

The proportion of poor single mothers who neither work nor receive welfare has increased sharply since 1996, according to census data analyzed by the Congressional Research Service.

Timothy Jeffries, the director of the Arizona Department of Economic Security, often declares his “love for the poor,” and with the one-year limit about to take effect, he says his agency is making vigorous efforts to help people find jobs.

But Democrats, outnumbered in the state Legislature, see it differently.

“It really feels like a hatred of poor people,” said state Rep. Celeste Plumlee, a Democrat who was on welfare for three years in the 2000s. “It’s just mean, that’s what it seems to me.”

Arizona is not the only state to shorten its time limit for benefits. On Jan. 1, Missouri lowered its lifetime limit to 45 months, from five years. The General Assembly, controlled by Republicans, overrode a veto by Gov. Jay Nixon, a Democrat, who said the change was “as harsh as it is unnecessary.”

In the first three months of this year, Missouri ended benefits for 2,780 households that had received cash assistance for 45 months or longer.

Ronald T. Haskins, who helped write the 1996 federal law as an aide to House Republicans, said that for some poor people, the erosion of cash benefits had been offset by increases in other programs, including the earned-income tax credit, nutrition assistance and Medicaid.

But Haskins said, “It is reasonable and appropriate to worry about mothers and children in families with no earnings and no cash welfare.”