Bernie Sanders is not going to be the Democratic candidate for President. Hillary Clinton needs fewer than 100 out of more than 700 remaining delegates to win the nomination. To be sure, the US Justice Department might bring criminal charges against Clinton for her e-mail server, which could cause her superdelegates to switch their votes and hand Sanders the nomination. As it stands, though, online betting markets place the odds of a Sanders victory at around 30-1. Although their candidate looks set to lose, a portion of Sanders’ supporters insist that they will refuse to vote for Clinton in the general election. Going by the mantle Bernie-or-Bust, these supporters insist they will either write in Sanders’ name or refuse to vote for any presidential candidate in November. They should do exactly that.
In the face of this vocal Bernie-or-Bust contingent, an increasing number of political commentators and politicians are losing patience with the Sanders campaign and its supporters. This week Paul Krugman described the raucous events in Nevada on May 14th as the “yelling of the Sanders dead-enders.” At New York Magazine Jonathan Chait depicted Sanders as the man who refuses to ‘get off the electoral bus,’ describing his continued presence as “maddeningly narcissistic.” Others fear that Sanders’ continued presence will split the Democratic Party, thereby undermining Hillary Clinton’s chances of victory in November. Along these lines Senator Barbara Boxer (D) has asserted that Sanders ought to moderate the fervor of his supporters in order to unify the party behind Hillary Clinton: “He should get things under control… We're in a race that is very critical. We have to be united. He knows that.”
In some ways, this Bernie-or-Bust group is fairly unremarkable. To be sure, the death threats that the Nevada Chairwoman Roberta Lange has received are unacceptable and have no place in modern politics. That being said, in May 2008, when Hillary Clinton was battling Barak Obama for the Democratic nomination, 12% Democratic primary voters said that if Clinton was not the nominee they would vote for John McCain instead of Obama. This compares to just 6% of current Democratic primary voters today who say they will not vote for Clinton. In light of the fact that the number of Bernie-or-Bust supporters is roughly half of the so-called PUMAs (“Party Unity, My Ass”) from two election cycles ago, the alarmism of Boxer’s comments seem to be overblown.
One thing that might justify Boxer’s alarmism is the increasing ideological divide within Washington. For some time political scientists have reported increased ideological sorting: fewer politicians reach across the aisle and cooperate with politicians from the opposing party to compromise over bipartisan legislation. During this time, as Thomas Mann and E. J. Dionne at the Brookings Institute note, “the Republican Party has moved much farther to the right of the political center than Democrats have moved to its left.” Together, the increasing ideological tenor of politics and rightward lurch of the Republican Party have raised the stakes of political defeat for the Democratic Party. If the Republicans take the White House in November, not only will Obama’s signature legislative achievement – the Affordable Care Act – be undone, but his climate change agreement in Paris is likely to be reversed, and seats on the Supreme Court will go to deeply conservative appointees. In the face of such politically dangerous opposition, the cost of Democratic Party disunity is just too high. Sanders supporters need to toe the party line to avoid such a calamity. After all, although Clinton might refuse to release the transcripts of her speeches to Wall Street, at least she will not repeal the Dodd Frank Act.
This argument from ‘negative partisanship’ is the strongest argument against Bernie-or-Bust. Even so, Bernie’s supporters still have a very good reason to refuse to vote for Clinton in November. If they don’t withhold support for Clinton, then Sanders' supporters risk losing all influence over the Democratic Party and any possibility for a social-democratic political agenda. Without a powerful left wing exerting tangible political pressure, the rest of the Democratic Party can trend towards the right or entrench itself in the center as broader political winds blow, and if this were to happen not even a dozen Democratic administrations will realize a Sanders-like political agenda. It's true that the costs of a single Republican administration starting next year might be very high, but the long term costs of a centrist or even right leaning Democratic Party could be even higher; cumulatively, it might diverge further from Sanders' social-democratic policy than a single Republican administration. Consequently, unless Sanders’ supporters are willing to place an electoral cost on the Democratic Party for moving too far to the right by withholding their support in the November election, then they undermine their power to change the party’s political agenda and risk long term harm.
In order to understand how Sanders supporters can become marginalized and impotent within the Democratic Party, consider the situation of African-American voters. In his 2010 book Uneasy Alliances, Princeton political scientist Paul Frymer describes African-American voters as a ‘captured constituency.’ Like Sanders supporters today, they suffer from a negative partisanship problem: Black incarceration has skyrocketed; since the 2008 crash African Americans have experienced the lowest economic gains of any ethnicity; and, even after the deaths of Eric Garner and Tamir Rice, Black men and children continue to be killed. Together these are strong grounds for criticism of the Democratic politicians and legislators that have overseen and failed to arrest these developments. But however little the Democratic Party has done to reverse these trends, the Republican Party would likely do less. Or do worse, as the proliferation of voter ID laws in red states suggests. Because of this dynamic the Democratic Party can rely on overwhelming African-American support without having to concede much in their policy program – there’s just no where else for Black voters to go.
Where could Sanders supporters go? Certainly not to the Republicans, and in a first past-the-post electoral system third parties rarely succeed. So Sanders supporters are stuck with the Democratic Party. In light of this, the only way Sanders supporters will realize the political agenda they believe to be right, is to move the Democratic Party to the left by implanting a real social-democratic agenda into the Democratic Party’s political platform. This shift in policy will only pass if the party is threatened by the prospect of electoral defeat, which can only occur if Sanders supporters are willing to withhold their support in November.
Sanders’ social-democratic supporters must avoid becoming another captured constituency and the slow bankruptcy of their political program that this status entails. In order to do this they have only one choice: Bernie-or-Bust.