COLUMBIA, S.C. — The searing issues of racism and poverty dominated the Democratic presidential campaigns Wednesday, as Sen. Bernard Sanders tried to drive a wedge between Hillary Clinton and black voters, who are poised to hand her another primary win in two days.
Mr. Sanders, who is losing black voters to Mrs. Clinton by a 3-1 margin, impugned her record championing minorities by linking her to welfare reforms that preceded a dramatic rise in poverty rates over the past two decades.
He said the 1996 welfare reform law that Mrs. Clinton supported as first lady helped cause the number of Americans living in extreme poverty to more than double from 636,000 then to 1.6 million today.
Mr. Sanders opposed the bill as a congressman from Vermont while Mrs. Clinton “worked hard to round up the votes for its passage,” he said at a press conference to draw attention to poverty issues.
“It’s a piece of legislation that I opposed because I thought it was going to hurt the weakest and most vulnerable among us, and what the record shows is that it did hurt the weakest and most vulnerable among us,” he said. “Secretary Clinton supported that legislation.”
Mr. Sanders also highlighted his lifelong fight against discrimination and poverty, noting that he joined the Rev. Martin Luther King Jr.’s 1963 march on Washington.
He mentioned King’s name a half-dozen times at the press conference, where he was flanked by two black South Carolina House members supporting his run.
Mr. Sanders took the swipe at his rival as he scrambled to connect with black voters in South Carolina, where Mrs. Clinton’s overwhelming support from minorities has helped her solidify a more than 20-point lead in most polls.
It’s part of a disturbing trend for the Sanders campaign.
At the Nevada caucuses Saturday, Mrs. Clinton defeated Mrs. Sanders soundly among black voters. The former secretary of state captured 76 of the black vote in the state, propelling her to a 6-point win overall.
Unless he breaks through with black voters, Mr. Sanders’ prospects appear dim as the Democratic presidential primary heads into Super Tuesday contests March 1, including Southern states Texas, Tennessee, Arkansas and Alabama, where minority voters again will be critical.
Darrell West, vice president and director of governance studies at the Brookings Institution, said Mr. Sanders must quickly make inroads with black voters or Mrs. Clinton will become unbeatable.
“The next few weeks will be decisive for Democrats,” he said. “Clinton already has one-quarter of the delegates needed for the nomination, mainly due to superdelegate support. Once she hits the 50 percent mark, it will be hard for Sanders to stop her because her nomination will look inevitable.”
Meanwhile, Mrs. Clinton worked to shore up her strong support among black female voters in South Carolina.
She echoed the same themes as Mr. Sanders but declared herself the candidate with the experience and the commitment to reverse poverty trends and vanquish what she described as “systemic racism” in America.
“We need a new and comprehensive commitment to expanding opportunities in black communities,” she said at a luncheon hosted by Alpha Kappa Alpha, the first black sorority, which has become a potent political force.
Mr. Sanders’ charges didn’t sway the women at the AKA luncheon in a Baptist megachurch in West Columbia, South Carolina.
“A lot of things changed since then. Things change and people change,” said Maggie Cooper, 33, a middle school teacher and mortician who attended the luncheon. “She knows the black community needs help, and she’s willing to help.”
Gardenia Coleman, 62, a retired state government worker and member of the sorority, said she was not impressed by Mr. Sanders’ time with King.
“Anybody can march,” she said. “Has he passed anything in order for that to be effective?”
Lee Miringoff, a political analyst and director of the Marist Institute for Public Opinion at Marist College, said Mrs. Clinton’s advantage with black voters stems from their 25-year relationship with each other.
“They know Hillary Clinton. Pictures of Sanders being arrested in 1963 aren’t going to change that,” he said.
In her luncheon speech, Mrs. Clinton noted statistics that show black women are three times more likely to die in childbirth and black children are more likely to die in their first year.
“Imagine if that was reversed. Imagine if a white baby was twice as likely to die before her first birthday than a black baby,” she said.
Mrs. Clinton said resources would “rush in” to address such problems in white neighborhoods. She said the crisis of contaminated water in predominantly black Flint, Michigan, wouldn’t occur in a white Detroit suburb.
She vowed to rush help to black communities across the country, including justice reform, better educational opportunities, more support for historic black colleges and universities and expanded access to health care.
“I want an election about real change that will make a difference in people’s lives,” said Mrs. Clinton.
⦁ Ben Wolfgang reported from Washington.