In the end, the four women decided that they could not be on the wrong side of a chance to elect a black president in 2008. They became Mr. Obama’s most loyal allies.

Now, women like Mrs. DeBose hope to end the long, unbroken line of men running the nation.

There are many reasons Senator Bernie Sanders of Vermont is polling as much as 30 percentage points behind Mrs. Clinton among black voters in South Carolina. Many African-Americans in the state say they do not know him well. Others bristle at his criticism of Mr. Obama’s health care overhaul, seeing it as an attack on the president’s legacy. Mr. Sanders wins points for his takedown of Wall Street and his vow to make public colleges free and health care available for all, but some wonder whether these ambitions are too lofty given the deeply divided Congress.

But one important reason for Mrs. Clinton’s support is that many black women, the drivers of the black vote, see this election as their chance to make up for the hard decision they had to make eight years ago. And in 2008, 98 percent of black women cast their ballots for Mr. Obama. Four years later, black women had the highest voter turnout of any group.

“I want someone with a womb in the White House at least one time before I die,” Mrs. DeBose said.

Later that night, around a dinner of smothered pork chops and fried chicken and waffles, Mrs. DeBose and her friends rattled off their many reasons for supporting the candidate they turned away from eight years ago. They called Mrs. Clinton the most qualified candidate in the race, and cited her stance on education and gun violence, as well as her many years of experience.