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Story highlights

Hillary Clinton isn't just looking for a win -- she's seeking her first breakout victory over Vermont Sen. Bernie Sanders in Saturday's South Carolina Democratic primary

In the last contest before Super Tuesday, Clinton will rely on the strength of her advantage with African-American voters

(CNN) —  

Hillary Clinton isn’t just looking for a win – she’s seeking her first breakout victory over Vermont Sen. Bernie Sanders in Saturday’s South Carolina Democratic primary.

In the last contest before Super Tuesday, the former secretary of state will rely on her advantage with African-American voters. Sanders, meanwhile, will look to prove he’s closed the gap among minority voters, setting himself on course to stay close in the last of the early-state contests.

Here are five things to watch Saturday:

1. Clinton’s margin

Clinton is widely expected to win – and potentially win big – in the Palmetto State.

Her margin of victory, though, is the crucial number to watch in order to forecast what lies ahead on Super Tuesday, when 11 states vote – turning what had been a state-by-state slog into a truly national contest.

Alabama, Arkansas, Georgia, Tennessee, Texas and Virginia are all Southern states with large portions of African-American voters, just like South Carolina. That makes South Carolina a critical test of Clinton’s strength in those places.

Sanders is focusing his efforts on five Super Tuesday states where he stands a better chance of winning: Colorado, Massachusetts, Minnesota, Oklahoma and Vermont.

If she wins in a blowout, Clinton can expect a big Super Tuesday. If she just ekes out a win, that would be more troubling for her campaign.

2. African-American turnout

In 2008, about double the number of black voters participated in South Carolina’s Democratic primary compared to 2004.

It was a huge component of then-Sen. Barack Obama’s runaway victory.

And if Clinton is to blow out Sanders on Saturday, she’ll need a large turnout among African-Americans as well.

At the heart of Clinton’s strategy to sew up the Democratic nomination is the notion that minority voters are a firewall of sorts that will prevent Sanders from accumulating the delegates he’d need to stop her.

Not every Democratic electorate, though, is as white as New Hampshire or as black as South Carolina.

Clinton doesn’t just need clear wins among minority voters; she needs them to turn out in force. And South Carolina will be the first test of whether her campaign has energized black voters enough that they will do just that.

3. Bill Clinton’s redemption

In 2008, it was ugly: The man once called the “first black president” alienated African-American voters in South Carolina after a series of outbursts against the Illinois senator who was set to become the actual first black president.

Particularly damaging was Clinton’s comparison of Obama to Jesse Jackson, who’d won South Carolina’s Democratic primary in 1984 and 1988. African-American leaders interpreted that as dismissive of the importance of the black vote.

Obama defeated Clinton by 29 points, a blowout that helped put him on the path to the Democratic nomination. Since then, the Clinton have repaired their relationships with the African-American community.

The best evidence that Bill Clinton’s damaging 2008 outbursts are healed comes from Rep. Jim Clyburn of South Carolina, the top-ranking African-American in Congress.

Clyburn wrote in his memoir that in 2008, Bill Clinton had phoned him at 2:15 a.m., calling him a “bastard” and blaming Clyburn for his wife’s defeat there.

This year, Clyburn has endorsed Hillary Clinton.

A strong Clinton win would signal that Bill Clinton – who has campaigned in South Carolina for his wife this year – has recovered from his past political wounds.

4. Sanders’ message

Sanders’ effort to reach out to African-American voters has been, at times, discordant.

Recently, he lashed out at Clinton in a BET interview, accusing her of cozying up to Obama in an attempt to pander to black voters.

Then, in a CNN town hall, he portrayed himself as a major Obama ally, hitting Donald Trump’s four-year-old quest for Obama’s birth certificate as racially motivated.

Sanders is particularly strong among young voters, white voters and men. But to secure the Democratic nomination, he’ll need to win over minority voters, too.

The South Carolina results will provide evidence of whether he is succeeding. His election-night speech – and then his appearances on Sunday morning news shows the next day – will reveal whether he has settled on the best strategy to achieve that goal.

5. The momentum primary

Clinton’s win in Nevada gave her just a few more delegates than Sanders – but that pales in comparison to the importance of the symbolic momentum it gave her campaign.

Going into the state, Sanders was riding a near-tie in Iowa and a blowout win in New Hampshire.

Leaving it, he faced with many of the same obstacles that have confronted him for months, just as the campaign calendar turned to terrain more friendly to Clinton.

South Carolina will settle a few more delegates, but it will also be an important moment for supporters of both candidates.

Just by keeping the state close, Sanders could reverse the damage of Nevada.

And keeping it close is exactly what he’ll try to do throughout the first 15 days of March. After Super Tuesday, he could pick up a few small states, but it’s six big ones – Michigan on March 8 and then Florida, Ohio, Illinois, North Carolina and Missouri on March 15 – that Clinton will be eyeing.

If Sanders can set himself on a path to wake up the morning of March 16 still within striking distance, it’ll be a major success, just as the campaign heads west to states he’s more likely to win.