After an up-and-down start to the 2016 presidential contests for Clinton, a sizable victory over Bernie Sanders on Saturday would be an emotional boost for her White House campaign and a chance to wipe away the fraught memories of her 2008 primary loss in the state.
It would also establish Clinton as the firm favorite among black voters, a crucial segment of the Democratic electorate, and set her up for a big delegate haul in next week's Super Tuesday contests in the South.
"The South Carolina primary is personally important to me because I want to send a strong signal that South Carolina is ready for change, ready for progress, ready to make a difference," Clinton said Friday during a rally in Columbia.
Sanders knows his prospects with South Carolina's heavily black Democratic electorate are grim. A longtime lawmaker from Vermont, where just about 1 percent of the population is black, Sanders lacks Clinton's deep and longstanding connections to the African-American community. He's tried to broaden his economic inequality message and touch on issues such as incarceration rates and criminal justice reform, but he has still struggled to gain traction in South Carolina.
Rather than devote precious time to a state he's prepared to lose, Sanders spent much of the past week in areas that vote in March. Even on Friday, the last full day of campaigning before South Carolina's polls open, Sanders began with a rally in Minnesota before heading south for a pair of events.
"We are fighting the fight for the survival of the working class of this country," Sanders said Friday morning at a rally in Hibbing, Minnesota.
In 2008, black voters made up 55 percent of the electorate in South Carolina's Democratic primary, according to exit polls. Clinton lost the state overwhelmingly to Barack Obama in a heated contest where her husband, former President Bill Clinton, was seen by some as questioning the legitimacy of the black presidential contender.
But South Carolina voters appear ready to forgive. The former president has been well-received by voters as he's traveled the state campaigning for his wife. Hillary Clinton also received the endorsement of South Carolina Rep. James Clyburn, the influential black lawmaker who stayed neutral in the 2008 primary, but was critical of the former president's comments.
"My heart had always been with Hillary Clinton, but my head had me in a neutral corner," Clyburn said as he announced his support for Clinton last week.
Even with a win all-but-guaranteed, Clinton's campaign sees South Carolina as an important jumpstart heading into a busy March. More than half of the delegates up for grabs in the Democratic race are on the table in the next month, with a heavy concentration one day next week - an 11-state voting bonanza known as Super Tuesday.
While Sanders has the money to stay in the race deep into the spring, Clinton's campaign sees an opportunity to build enough of a delegate lead to put the race out of reach in the coming weeks.
Clinton has a one-delegate edge over Sanders after her narrow win in Iowa, her sweeping loss in New Hampshire and a five-point victory in Nevada. She also has a massive lead over Sanders among superdelegates, the Democratic Party leaders who can throw their support behind a candidate of their choice, regardless of how their states vote.
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