While the global ascendance of insurgent anti-establishment political forces and the consequent threats to democratic norms have been widely acknowledged by scholars of democracy, the efficacy of gate-keeping tactics when dealing with populists, alongside the definition of “populism” more broadly, remain fields of significant debate. Should democratically-minded leaders engage with populists to further expand representation, even to so-called “angry” voters, or should they condemn populists and their sympathizers entirely as existential threats to democracy? Should the intraparty gates to presidential competition be fortified, widened, or torn down? I argue that the 2016 U.S. presidential election suggests that the concept of “gate-keeping” has become increasingly problematic within modern American presidential politics. Advances in social media technology now allow charismatic candidates to bypass what Muller calls “intermediate institutions” and instead pursue “direct representation,” perhaps best represented by the reliance by both Trump and Sanders on social media platforms like Twitter and Reddit (What is Populism, 35). This strategy, in turn, provoked a legally questionable and politically counterproductive tactic by Clinton: her campaign’s decision to coordinate with the Correct the Record Super PAC. While her campaign much more skillfully utilized legacy media outlets and naturally received the vast majority of newspaper endorsements, these strategies also proved ultimately insufficient. Most importantly, party-driven attempts at gate-keeping were only partially and asymmetrically successful at excluding populist-type figures, hindering an anti-establishment pluralist within the Democratic primary (Sanders) and emboldening a nomination and then presidential victory by an anti-establishment, anti-pluralist Republican populist (Trump).
I borrow Muller’s qualification here of Sanders as explicitly “not a left-wing populist,” despite his embrace of anti-elitist rhetoric (What is Populism, 93). For this scholar, being critical of elites is a “necessary” but “not a sufficient condition” for identifying populist politicians (What is Populism, 2). While it is critical to stress that Sanders was allowed participation in several debates and failed to win the popular vote in the Democratic primary, this does not rule out gate-keeping; perhaps the party elites within the “smoke-filled rooms” of intraparty politics that Levitsky and Ziblatt mention simply behaved less blatantly? The number of debates was much fewer than previous primary seasons, suggesting some incumbent-protecting deviance from party norms. Furthermore, the “invisible primary” of “elected officials, activists, [and] allied interest groups” remained relevant in a primary system still decided in part by superdelegates, who include incumbent Democratic elected officials (How Democracies Die, 37, 51).
Levitsky and Ziblatt concur with Muller in identifying the “explosion of alternative media, particularly cable news and social media,” as a “major factor” in the weakening of gate-keepers (How Democracies Die, 55). In an apparent effort to overcome this disadvantage, the Clinton campaign coordinated with a Pro-Clinton Super PAC that spent $1 Million USD “creating hundreds of fake accounts, which then place[d] campaign propaganda all over the web as if it came from ordinary supporters” in order to seemingly create the appearance of grassroots support on social media. This ostensible “fact-checking” effort was soon characterized as blatant astroturphing, a “psychologically manipulative” political approach that “instead of building support the hard way, simply buys it” (CurrentAffairs). This tactic shockingly resembles propaganda efforts by Russian president Vladimir Putin, whose government hires “hundreds of Russians to post pro-Kremlin propaganda online under fake identities, including on Twitter, in order to create the illusion of a massive army of supporters” (CurrentAffairs).
Ultimately, this astroturph effort was an obvious failure to engage with anti-establishment Sanders supporters on the part of the Clinton campaign and its allies; after all, Correct the Record was premised on the need to counter vicious Sanders-supporting trolls online. Instead of reaching out to these populist sympathizers (even if Sanders is not quite a populist), these campaigners instead chose to categorize his supporters as “Bernie bros” and even as an “angry white male cult,” despite a poll finding that millennial women expressed nearly twice as much support for Sanders than for Clinton, at “61%-30%,” much higher than the male millennial numbers. In writing about dealing with populists, Muller warns precisely against this by writing that to “treat the angry and frustrated as potential patients for a political sanatorium” is “to neglect a basic democratic duty to engage in reasoning” whilst repeating “exclusionary gestures” (What is Populism, 16). Voter frustration is a natural part of the democratic process and should be engaged, rather than dismissed or denigrated (What is Populism, 16). By attempting to exclude and dismiss populist opposition within their own party, Clinton campaign allies poured fuel on the populist flames of 2016.
In summary, I argue that engagement is critical in order to at least attempt to connect with disaffected voters with populist leanings. Gate-keeping reliance is naive in a modern world where the barriers to communications are minimal and alternative media thrives. While Levitsky and Ziblatt argue that “had Republican leaders publicly opposed Trump,” the “Republican electorate would have split—some heeding the warnings of the party leadership and others sticking with Trump,” (How Democracies Die, 71) Muller argues contrarily that “all political actors other than the populists [colluding] to exclude the latter,” if anything, only “strengthens the credibility of populists in claiming that the established parties are forming a “cartel” targeting them and their supporters (What is Populism, 82). As with the Correct the Record campaign, broad institutional support, be it from an aggressive Super PAC or from party leaders, may both further weaken the non-populist’s reputation while emboldening the populist opposition. Gate-keeping is thus no longer realistic in hyperpolarized American elections; it is a self-defeating and unsustainable strategy.
https://www.salon.com/2016/06/10/the_democrats_party_derailed_bernie_how_the_establishment_has_worked_to_discredit_sanders_movement/  Müller, Jan-Werner. What Is Populism? University of Pennsylvania Press.  Levitsky, Steven, and Daniel Ziblatt. How Democracies Die. London: Penguin.