10 cnn town hall 0226 warren
Warren: Will run until convention even if behind in delegates
02:51 - Source: CNN

Editor’s Note: Julian Zelizer, a CNN political analyst, is a professor of history and public affairs at Princeton University and author of the forthcoming book, “Burning Down the House: Newt Gingrich, the Fall of a Speaker, and the Rise of the New Republican Party.” Follow him on Twitter: @julianzelizer. The views expressed in this commentary are his own. View more opinion at CNN.

CNN  — 

Saturday will be a big day in South Carolina. With so many candidates in the Democratic competition, most of whom have sizable blocks of support, each state contest so far has turned into a hugely consequential day of voting. And the South Carolina primary will be no different.

For former Vice President Joe Biden, South Carolina means everything. The candidate whom many have called the “most electable” in the bunch struggled in Iowa, New Hampshire, and – to a lesser extent – in Nevada. Not only did he lose, but he lost badly in Iowa and New Hampshire, and placed a distant second in Nevada.

Meanwhile, Vermont Sen. Bernie Sanders has propelled himself to the top of the heap, and with the rest of the candidates dividing up the vote, the Democratic Socialist from Vermont now finds himself in a position to win the nomination.

If Biden does not win in South Carolina, the state his campaign thinks will help him rebound, it could easily be the end of the race for him. South Carolina has been his so-called “firewall,” and now that firewall has to hold. If the day ends with Sanders on top, or even a very close second, there will be considerable pressure on Biden to step down. The stakes are particularly high since the former vice president has not spent nearly as much time in other Super Tuesday states

A poor showing in South Carolina would dampen Biden’s organizational enthusiasm and fundraising. With former New York City Mayor Michael Bloomberg ramping up his television ad buys, and with Massachusetts Sen. Elizabeth Warren and former South Bend Mayor Pete Buttigieg showing no signs of packing up, the next few weeks could be rough if South Carolina doesn’t live up to expectations for the Biden.

Fortunately for Biden, the last few days have been promising. He stood his ground on the fractious debate stage, displaying the kind of energy and righteous anger that have been lacking from many of his campaign performances. He had an extraordinarily moving moment during CNN’s town hall, tearing up as he responded to a question from a pastor whose wife was killed in the 2015 Charleston church shooting. And South Carolina Rep. Jim Clyburn, an influential voice in the state, offered Biden his formal endorsement.

If Biden can turn all of these good moments, as well as months of organizational efforts, into a decisive victory in South Carolina, he will put himself in much stronger standing for the next few rounds of voting.

n other words, his candidacy will seem plausible again. With many Democrats still fretting over the electability of Sanders and seeking a safer bet – desperate to avoid a second term of President Donald Trump at all costs – Biden still brings the gravitas and experience that voters may feel would make him better at governing than Trump. He is the most-known quantity in this campaign, and if he can survive the nomination process, he could pose a tough challenge to the President in swing states and suburban constituencies that are on the fence.

The other candidates also face high stakes moment in South Carolina, though the contests on Super Tuesday will be more important for them.

If Sanders can pull out a victory or come in a close second on Saturday, he will be in an excellent position to lock in the frontrunner position by the end of Super Tuesday. Such an outcome would give him the momentum to secure a huge number of delegates in California and Texas, making the others feel very far away from winning the nomination.

For Sanders, coming in a strong second would be almost as good as winning. It would show once again how formidable his campaign is, while encouraging Biden to stay in the race and thus continuing to split the non-Sanders delegate count.

A strong performance by Warren, who has promised to stay in this race until the convention, provided no candidate has received a delegate majority, could bolster her standing as a real progressive alternative to Sanders. She could be the champion of progressive causes in a way that generates less anxiety among Democratic leaders.

Obviously, a solid turnout for Minnesota Sen. Amy Klobuchar, who continues to impress on the debate stage but still isn’t pulling in large number of delegates, would keep her alive for Super Tuesday. She represents the most interesting, moderate alternative to Bloomberg and doesn’t carry as much baggage of the former mayor.

Tom Steyer, who doesn’t really have much of a chance of amassing many delegates, could show his chops if he wins enough votes from younger African American voters to undercut Biden’s total. That could make him a key player in the weeks ahead.

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    Buttigieg also has a great deal to prove. His goal should be to do better than expected in South Carolina among African American voters, demonstrating that he does have the capacity to secure the support of core Democratic constituencies, despite what the early polls have shown. This would expand the number of political leaders and voters who see him as a candidate with the potential to unite and mobilize the Democratic coalition.

    But, without a doubt, the most important story on Saturday will be Biden. This primary is truly a make-or-break moment for him. If he wins big, Biden brings his campaign back to life and improves his odds to make it until the convention. If he doesn’t, it could be the first step in narrowing the number of Democrats who are vying to win this nomination.