Editor's Note: (Sally Kohn is an activist, columnist and television commentator. Follow her on Twitter: @sallykohn. The opinions expressed in this commentary are solely those of the author.)
(CNN) If Bernie Sanders' performance in New Hampshire, Iowa and Nevada was a shot across the bow of his nervous opponent's ship, then Hillary Clinton's landslide victory in South Carolina is the equivalent of a massive missile defense shield on that bow.
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"Rest assured," voters in South Carolina seemed to say to Clinton, "you got this."
Hillary Clinton's South Carolina victory shows that her candidacy is durable, and that durability is just what she needs to survive the challenge from Sanders and finally prevail.
Now Clinton, whose campaign just days ago seemed deflated, heads toward Super Tuesday with a strong wind at her back. The South Carolina outcome does not decisively end the entire primary contest, but it presages what may be another strong outcome for Clinton this coming Tuesday.
Early estimates based on CNN exit polls show Clinton with as much as a 3-to-1 lead over Sanders. While those exit polls show that Sanders still won a majority of South Carolina's white voters (by a 20 point margin), support from 80% of African-Americans who turned up at the polls on Saturday helped hand Clinton her overwhelming victory in the state.
Black voters made up a greater percentage of the overall voting base in Saturday's primary, compared with the 2008 election, according to entrance polls. It's still unclear whether that was because more black voters turned out this year than in 2008, or fewer white voters turned out this year-- but the shift, along with Clinton's commanding lead among black voters, appears to have helped the outcome.
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Also, while CNN exit polls show Sanders still won among younger voters, they made up a fairly small share (15%) of the primary electorate. It's also worth noting that, in South Carolina, Clinton won among voters across the ideological spectrum -- including those who, in exit polls, identified themselves as "progressive."
Now all eyes will turn to Super Tuesday. This Tuesday, March 1, Democratic voters will hold primaries in 11 states: Alabama, Arkansas, Colorado, Georgia, Massachusetts, Minnesota, Oklahoma, Tennessee, Texas, Vermont and Virginia. Democratic voters in American Samoa will also caucus on Tuesday and Democrats living abroad will begin casting their votes. In total, 865 delegates are up for grabs on Super Tuesday — more than in all of the Democratic primary and caucus contests combined thus far.
Sanders has trained his eyes on five Super Tuesday states, Clinton has focused on six. Yet the ones in Clinton's sights, and where she looks -- at this point -- likely to prevail, have more delegates than those on which Sanders is concentrating. In other words, millions of Americans may still be feeling the Bern, but the cold water of simple math may ultimately extinguish the flame.
That's not to say that Sanders is out yet, or that his campaign has been for naught. It is arguably entirely because of Bernie Sanders that so much of Hillary Clinton's campaign policy and rhetoric has steadily shifted its focus to economic inequality and the yawning wealth and opportunity gap in America.
Because Clinton needed such a decisive victory in South Carolina, she was forced to hone in on courting African American voters with real seriousness and attention, making her case to draw them to the polls, rather than counting on blacks' traditional support of Democrats. And when Black Lives Matter pressed both Sanders and Clinton to improve their analysis and positions on systemic racism, Clinton had not just a moral but practical motivation to do better.
Beyond this, Sanders raised issues about Clinton, such as campaign donations from Wall Street and past votes on banking policy for which Clinton should be held to account. Had he not done that she would likely have downplayed them.
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Even if he doesn't prevail, Sanders has been the stone against which Clinton has honed and sharpened her own candidacy. Just having to debate him, having to work harder to explain her positions and connect with voters, has made Hillary Clinton a better candidate.
The South Carolina results, which are still to be analyzed, suggest some other potential bright spots for Clinton and challenges for Sanders. Despite conservative attempts to smear Clinton, in exit polls, a majority of South Carolina's Democratic primary voters said Clinton is honest and trustworthy—and ranked her as more so than Sanders.
And by a wide margin, Democrats in South Carolina say they think Clinton will handle a Supreme Court nomination better than Sanders — an issue that may continue to rise in voters' minds.
But perhaps most encouraging for Democrats in general is that a majority of South Carolina Democrats said they would be satisfied whether Clinton or Sanders wins the nomination. Which reflects far greater unity, and thus focus, than you'll find at the circus on the other side of the aisle.
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Editor's note: This article gives a corrected figure for the Democratic delegates to be chosen on Super Tuesday.