Ralph Nader: Why Bernie Sanders was right to run as a Democrat

During a recent town hall in Columbus, Ohio, Sen. Bernie Sanders said the unthinkable. At least, you would have thought he did, judging by the response of several Democratic operatives. Sanders was deemed “extremely disgraceful” by Donna Brazile, vice chair of the Democratic National Committee, and “a political calculating fraud” by Brad Woodhouse, a former DNC communications director.
What was his crime? The old-fashioned Rooseveltian New Dealer had answered a question about why he is running as a Democrat, instead of as an independent, with typical candor: “In terms of media coverage, you had to run within the Democratic Party,” he observed, adding that he couldn’t raise money outside the major two-party process.
As one of the more successful third-party presidential candidates in recent U.S. history, I know firsthand the obstacles Sanders might have faced if he had run as an independent... 
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Just appearing on the ballot is a challenge for independent candidates. While any Democrat or Republican who wins their party’s nomination is guaranteed a place on general-election ballots nationwide, smaller parties must, in many states, petition election officials to be listed. And that is a delicate process, easy for the major parties to disrupt. Their operatives have a number of tools at their disposal to knock third-party candidates off the ballot, render their campaigns broke, and harass and ostracize them.