This old chestnut was raised in another thread. It deserves reexamination.
Those who hate America's democratic system---which includes Russia, Donald Trump, Trump's supporters, Kari Lake and her fellow losers---all have their reasons to sow the seeds of voter distrust and discredit our elections.
Bernie Sanders says his 2016 team saw effects of Russian anti-Clinton campaign
In an interview with the Des Moines Register, Sanders described how an aide handling his social media accounts noticed an uptick in “horrific and ugly things” directed at Clinton beginning around September 2016 — long after the Democratic nomination had been decided, and while Sanders himself was traveling the country campaigning on her behalf.
Sanders, a U.S. senator from Vermont, said. "We knew that they were trying to sow division within the American people. In my case, it was to tell Bernie supporters that Hillary Clinton is a criminal, that Hillary Clinton is crazy, that Hillary Clinton is sick — terrible, terrible ugly stuff — and to have Bernie Sanders supporters either vote for Trump or Jill Stein or not vote at all."
For a scholarly assessment of the 2016 primary read the report, Was the Democratic Nominations Rigged? A Reexamination of the Clinton-Sanders Presidential Race, of which these are excerpts.
The Rules Benefited Sanders, not Clinton
The ultimate irony of the 2016 presidential contest was the fact that the Democratic rules benefited Bernie Sanders far more than Hillary Clinton. Two election rules in particular provided critical assistance to the Sanders campaign. The first was the Democratic Party's award of delegates on a proportional basis, which enabled Sanders to come away with delegates even in states he lost by hundreds of thousands of votes. The second pro-Sanders rule was the large number of "open" primaries and caucuses in the Democratic race, which permitted independent voters-a key Sanders constituency-to participate in the Democratic nomination process.
The overall vote totals revealed the extent to which independent voters boosted the Sanders campaign. In the 2016 nomination race, Clinton carried 66% of registered Democrats, whereas Sanders only received 33% of the Democratic vote. But Sanders dominated among independent voters, which enabled him to drive down Clinton's total share of all votes cast (independents and registered Democrats combined) to 55%.289 In other words, if the state Democratic parties had closed their contests to only permit registered Democrats to participate, Clinton would have won the nomination much earlier.29 0 Open primaries thus kept Sanders in the race despite the fact that he lost registered Democrats by a 2-to-I margin. Instead of bemoaning the Democratic rules, therefore, Sanders had grounds to thank the Democrats for holding their nomination contests open to independent voters and for establishing a delegate system so congenial to candidates who finished a distant second in the popular vote. Source: (Pages 347 & 351) Link below