Now that Bernie Sanders is incontrovertibly the front runner in the race for the Democratic Party nomination for President, the worry that he will launch an insurgent independent bid for the presidency is no longer heard from his detractors very often. That would surely change if the DNC successfully undercuts him by continuing to foster and aid Michael Bloomberg in his meteoric rise to the top of the field. If Bloomberg were to clinch the nomination in a messy convention floor battle, or if Buttigieg or Klobuchar were to suddenly take the lead from Sanders via backroom delegate trading, Sanders’ supporters would no doubt cry foul. Some would even join with his detractors in floating the idea of an independent bid for the White House, though for the opposite reasons of course.
However tempting as it might be to imagine such a scenario, Sanders would not run as an independent if he loses the primary for one simple reason: he doesn't yet have the broad-based financial security needed to launch a successful independent bid. He has tens of millions of dollars, sure enough. But the DNC has hundreds of millions of dollars, and a candidate like Bloomberg can match that amount. Sanders would get crushed.
Sanders knows this, and it is one of the main reasons why he didn’t try for an independent bid in 2016 either. The Democratic Party is an immensely powerful organization, and the control that the ruling donor class exerts on American politics via organizations like the DNC and super PACs should not be underestimated. In order to win, Sanders would likely have to violate his oath never to take money from big donors, and he would lose all of his carefully fostered credibility if he did so. The fallout from such hypocrisy would probably end his career.
Sanders’ reliance on small donors is legendary. He relies on small contributions in order to avoid becoming beholden to the DNC donor class, who have controlled the party for the last 50 years. Things weren’t always this way. Gaining funding via mass movements at the grassroots level used to be the norm for presidential candidates and their campaigns. Before the destruction of machine politics in the post-war era and the subsequent rise of primaries, reliance on big-money donors was not the norm. Sanders’ campaign is in part a demonstration that a new era of mass movement politics is dawning, and he would not want to squander that by turning around and accepting big-money donors.
However, there is another way Sanders could go rogue should he lose the nomination. Instead of launching an independent bid, Sanders could take his sizeable base of supporters out of the Democratic Party and launch a third-party bid. There is precedent for such a move. In 1912, after losing the race for the nomination for the Republican Party, Teddy Roosevelt formed the short-lived Progressive Party. He lost the general election, however, and Sanders probably would too if he chose that route for one simple reason: the two major parties have created a uniquely harsh electoral environment for third parties. Supposing that Sanders were successful in peeling off a sizeable minority of the Democratic Party base to form his own third party, he would still have to organize campaigns and get on ballots across all 50 states. He would have to do this while facing the very real accusation that his party would ensure Trump’s victory via the Spoiler Effect, namely that his third party would take votes away from the Democratic Party candidate and therefore ensure Trump’s victory in November. Potential recruits would quickly develop animosity toward Sanders, as they have toward all third party candidates throughout history.
Sanders also has several positive incentives for refraining from an independent or third-party bid. Sanders is very interested in developing a movement that will last far beyond his presidential bid. So far, his campaign has been associated with the DSA in this effort. Right now, the DSA is in a period of expansion and even managed to field several congressional candidates who are known as the Squad. A break with the Democratic Party would test the support such a movement might otherwise have among Democratic voters this critical time in the nascent movement’s development. If Sanders wants his vision to outlast him, he should not make moves that might alienate voters who might otherwise vote for DSA candidates at the local and regional level. After all, these candidates are already laying the foundation for a true Democratic Socialist Party. This is a strong incentive to stay away from jumping the gun and launching his own third party bid prematurely.
Tying this back in with the problems of accepting big money donations, the only way to build the kind of grassroots mass movement that Sanders and the DSA want is to avoid getting sucked into the big money trap that the Democratic Party has set for third party candidates. The Democratic Party uses its massive war chest to exert down-ballot control over politicians. Candidates who stray from the party line will be cut off from donors, and without a mass movement to support them, they will not find funds outside of the Democratic Party either. Currently, this situation is enraging the Left and Sanders can use that rage. The Left feels excluded from the party, and, contrary to what many moderate liberals seem to believe, this is why Warren, AOC, and Sanders supporters are angry at candidates like Biden and Buttigieg, who openly support this antidemocratic donor system. Leftist anger is not about identity politics or purity tests. It's about the perception that the Democratic Party has been captured by an oligarchic cabal of elites who have no reason to "invest" in candidates whose platforms do not offer a "return" on their investment. Sanders' grassroots movement is an attempt to break this gridlock within the party.
To understand why Sanders will not go rogue if he loses the race for the nomination one must understand the larger project behind Sanders’ campaign. He is building a movement that will grow even if he loses the race for the presidency. The only way to continue as an independent would be to accept the help of a large donor since the mass movement is not yet large enough to go up against the DNC in the financial game. That would, of course, violate the principles upon which his mass movement is constructed. Similarly, he would not launch a third party prematurely while the movement is too small to sustain more than a handful of representatives in the House. Instead, if Sanders does lose the race for the nomination, he will in all likelihood do what he did in 2016: endorse the nominee and exit the race graciously.