Bernie is crashing the American party system. That's why establishment Democrats are so afraid of him

Since Bernie Sanders extended his winning streak to seven out of the last eight states on Tuesday with a decisive victory in Wisconsin, the race has quickly turned into a grudge match reminiscent of the 2008 contest between current frontrunner Hillary Clinton and President Barack Obama. Presidential qualifications have been debated, tragedies have been politicized, and loyalties have been questioned. Indeed, Clinton has become increasingly vocal about Sanders’ apparent lack of devotion to the Democratic Party.

“He’s a relatively new Democrat,” said Clinton in an interview with Politico magazine on Wednesday. “I’m not even sure he is one. He's running as one. So I don't know quite how to characterize him. I'll leave that to him. But I know there's a big difference between Democrats and Republicans, and I know that Senator Sanders spends a lot of time attacking my husband, attacking President Obama, you know, calling President Obama weak and disappointing, and actually making a move in 2012 to recruit somebody to run a primary against him. I rarely hear him say anything negative about George W. Bush, who I think wrecked our economy, just not to put too fine a point on it.”

A few days earlier, at a Democratic event in Wisconsin, Clinton declared that she is a “proud Democrat” who supports Democrats “up and down the ticket,” suggesting that Sanders, who was a longtime Independent before announcing his candidacy last year — even though he has always caucused with Democrats — is not quite loyal enough to be the Democratic nominee. It is a point that resonates with certain Democrats, especially donors and officials, who consider Sanders to be an outsider. But for many voters who are fed up with the party establishment, it is a part of the Senator’s appeal.

In March, Sanders candidly explained why he chose to run as a Democrat instead of an Independent during an MSNBC town hall:

"We did have to make that decision: Do you run as an independent? Do you run within the Democratic Party? We concluded — and I think it was absolutely the right decision — that A) in terms of media coverage, you had to run within the Democratic Party. Number two, that to run as an independent, you need, you could be a billionaire. If you’re a billionaire, you can do that. I’m not a billionaire. So the structure of American politics today is such that I thought the right ethic was to run within the Democratic Party.”

After months of being largely ignored by the mainstream media, one can only imagine the lack of coverage Sanders would have received as a non-celebrity/non-billionaire Independent candidate. Not surprisingly, this explanation offended some of the party faithful, who consider party loyalty to be a moral imperative in this hyper-partisan epoch. But more and more Americans are rejecting this kind of thinking, and rigid party loyalty — or lack thereof — is not only an area of divergence between Sanders and Clinton, but their supporters.

Indeed, for Sanders, Independent voters have been key to his ongoing success, and in at least three states (New Hampshire, Michigan, Oklahoma), they probably carried him to victory. Throughout the primaries, about 30 to 50 percent of support for Sanders has come from Independents, according to exit polls, while Clinton has been more dominate among Democratic voters.

Likewise, in general election polls, Sanders does much better with Independents than Clinton does against Republican candidates. According to the latest national poll from Quinnipiac University, for example, Sanders defeats Trump 52 to 36 percent among Independents, while Clinton loses 39 to 40 percent.

In many ways, Sanders is running against the two party system that has dominated American politics for most of its existence, yet he is doing it as a Democrat (which, as he stated, was a practical decision). Sanders is the longest serving Independent in congressional history, and if nominated, he would be the first major-party presidential candidate who is, strictly speaking, not a true member of the party. (This is one reason why Clinton has a towering superdelegate lead.)

Last week, the actress and Sanders surrogate Susan Sarandon ruffled many Democrats when she told Chris Hayes during an interview that some Sanders supporters may not vote for Clinton if she is nominated, and that “some people feel that Donald Trump will bring the revolution immediately, if he gets in.” Of course, her quote was taken out of context by the media to imply that she would vote for Trump over Clinton, which she later denied. (If anything, she implied a write-in for Sanders.)

While the majority Sanders supporters would presumably vote for Clinton (or against a Republican) if she gets the nomination, Sarandon is correct that there is a notable segment that would not. In a newly released poll from McClatchy-Marist, about 1 in 4 Sanders supporters said they would not support Clinton in the general — which is slightly lower than the one-third in a Wall Street Journal/NBC News survey from March.

Of course, it’s not just Sanders supporters who are tired of the major parties. The simultaneous rise of Donald Trump indicates an electorate that has become increasingly disillusioned with both parties. Today, more Americans describe themselves as Independent than either Republican or Democrat, and view one party or another as the lesser of two evils. Neither the Democrats or Republicans are free from the corrupting influence of special interests, and both Sanders and Trump have benefited from their lack of big donor funding. (Trump may be a demagogue, but he does not appear to be anyone’s puppet.) Moreover, according to a Gallup survey from last September, about six in ten Americans believe that a third political party is needed for adequate representation.

Still, the two-party system that has endured for most of the country’s existence will not be easily overcome — even if popular will demands it. Sanders seems to believe that reform within the Democratic party is a more feasible option for the American left than third party politics (which some on the left vehemently disagree with). He has run as a Democrat because he knows how tilted the American political apparatus is towards the two major parties, and this is a political reality that the left cannot ignore.

It is important to understand that America’s national electoral system is fundamentally hostile to third parties. The first-past-the-post (a.k.a. winner-takes-all) system, which encourages tactical voting and gerrymandering, inevitably leads to political duopoly. In order to make third parties viable in American politics, this electoral system would have to be overhauled and replaced with a form of proportional representation, which is found in many other democratic nations. (Different systems of proportional representation can be found on the website of the advocacy group FairVote.)

For presidential and Senate elections, an instant-runoff voting system in which voters can rank their candidates in order of preference would help eliminate the spoiler effect, which prevents people from voting for third party candidates who they may be partial to. If, for example, Sanders ran as an Independent in a general election between Clinton and Trump, voters who prefer Sanders over Clinton (but fear a Trump presidency) could list him first and Clinton second, so that if Sanders came in third and was eliminated their votes would automatically go to Clinton, rather than helping Trump.

Without these reforms, along with the elimination of big money from politics and ongoing popular movements that challenge the Washington establishment, it is hard to imagine America’s political duopoly coming to an end. For now, however, it is the establishment wings within the parties that are being confronted. Whether the Sanders movement can push the Democratic establishment to the left in the longterm remains to be seen — and this will help determine whether a third party is truly needed for a progressive movement in America.