05:44 - Source: CNN
Mark your calendar: 400 days until Iowa Caucuses

Editor’s Note: Dean Obeidallah, a former attorney, is the host of SiriusXM radio’s daily program “The Dean Obeidallah Show” and a columnist for The Daily Beast. Follow him @DeanObeidallah. The opinions expressed in this commentary are his own. View more opinion articles on CNN.

CNN  — 

On Saturday, Twitter was abuzz with the news that Bernie Sanders, the independent Vermont senator, might be “imminently,” as Yahoo News reported, jumping into the 2020 race for president.

But it was readily apparent from the trending hashtag #NeverBernie that Sanders’ entrance into the 2020 race would be far different and likely even more challenging than 2016.

When Sanders announced in May 2015 his run for the 2016 Democratic presidential nomination, he was only viewed unfavorably by 12% of those polled by Gallup.

His unfavorable rating, however, in that same poll in late 2018 is closer to 40%. And more than that – and this truly surprised me – was the level of opposition and even anger directed at Sanders by some of my fellow progressives on Twitter on Saturday.

In 2016, I supported Sanders in the Democratic presidential primary. After Hillary Clinton became the nominee, however, I became a surrogate for the Clinton campaign, speaking on her behalf to the Arab and Muslim American community since I’m a member of both.

So when I speak of the reaction to Sanders’ possible run in 2020, I do this as someone who supported him in the past for championing issues that leading Democrats were not discussing at the time – from railing against the “billionaire class” – which he declared “controls the political life of our country” – to speaking of Palestinians as human beings who not only deserve their own state but should also be treated with “respect and dignity.”

Sanders’ greatest impact, though, is likely on the issue of a single-payer health-care system which he dubbed “Medicare for All.” During the 2016 campaign, Clinton rejected the proposal, even running an ad slamming it where she declared: “The American people can’t afford to wait for ideas that sound good on paper but will never make it in the real world.”

Flash forward and a 2018 Reuters poll found that not only do 85% of Democrats support “Medicare for All” but many of the leading Democratic presidential candidates have embraced it, including Senators Elizabeth Warren, Kamala Harris and Kirsten Gillibrand.

Despite that, as I learned first-hand Saturday, there are many Democrats – even past supporters – who either are looking for a new candidate in 2020 or passionately oppose him. There were several distinct themes that emerged among the countless people who were tweeting in connection with the #NeverBernie hashtag.

The first thing that I noticed was anger over the possibility that Sanders could consider running as a Democrat again. Countless people raised the point – which is certainly valid – that Sanders had long identified as an Independent and only became a Democrat to be able to run in the 2016 Democratic primary contests. Then in 2017, Sanders declared that he was running for re-election to the US Senate as an Independent, rebuffing efforts from Democratic Party leaders to formally join the Democratic Party.

That was the main source of contention among self-identified progressives, but close behind was the belief that Sanders had cost Clinton the election in 2016.

While others made it clear they held no personal animus towards Sanders, they expressed fears that if Sanders ran it would reopen the wounds of the Hillary-Bernie fight we saw in 2016. As these people noted, in order to defeat Trump in 2020, progressives must be united. And they were concerned that a Sanders’ candidacy could undermine that.

What was also unexpected were the number of people on Twitter – some I have interacted with or known for years – who said that they had supported Sanders in 2016 but simply wanted someone younger in 2020. One friend, who was truly a big Sanders supporter in 2016, tweeted that if Sanders, who is now 77, is elected he will be the oldest president ever elected and for this reason he preferred a younger candidate.

There were several other themes raised by those who opposed Sanders such as the way he dragged his feet to release his tax returns in 2016 and the fact that he opposed sanctions against Russia in a 2017 Senate vote. In a statement, Sanders said that he supports sanctions on Russia for interfering in our 2016 election but voted against that sanctions bill because he had concerns it would undermine the Iran nuclear deal since the bill had proposed sanctions against both Iran and Russia.

Another issue that clearly upset many progressives were the actions of the so called “Bernie Bros,” purported Sanders supporters, who had reportedly engaged in harassment of Clinton supporters and reporters during the 2016 campaign.

Some of these “Bros” spewed hateful and often sexist comments. While Sanders did denounce the Bernie Bros tactics as “disgusting” in 2016, for many those words weren’t enough.

Obviously, there are countless people who still passionately support Sanders today. Indeed, a December CNN poll of Iowa Democrats found Sanders in second place behind Joe Biden. And if Sanders runs in 2020, he could very well win the nomination.

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    The stark reality is that in 2020 – as opposed to 2016 - -the field is not just Sanders versus Clinton. Currently, there are eight confirmed candidates, but the number could go up to 14 candidates or higher, many of whom will be espousing positions just as progressive as Sanders.

    And, clearly, if Sanders enters the 2020 race he will have some built-in opposition that he didn’t have when he first ran in 2016. But win or lose, Sanders’ legacy will be that he played a major role in moving the Democratic Party to the left, especially on health care, which may just help the ultimate Democratic presidential nominee win the White House in 2020.