The only way to beat President Donald Trump in November is for Democrats to be self-critical about what went wrong in 2016 and fix those mistakes. We failed to connect enough with the working-class voters who should be the backbone of our party. We didn’t get enough young people and voters of color out to the polls. And we underestimated the power of an energized political movement — both on the left and the right.

Sen. Bernie Sanders, I-Vt., and not former Vice President Joe Biden, is the antidote to each of those problems in 2020 — but political pundits have all but declared the Democratic primary over and the latter the winner.

That, despite the fact that there are still millions of ballots to be cast and more than 2,300 delegates to be awarded as of Wednesday morning. But they are foolish to dismiss my friend Bernie so easily. Remember this time last year? CNN had him sixth in its rankings of Democratic contenders, and they weren’t alone in counting him out of the top tier. Still, he’s once again proven conventional wisdom wrong and is still very close in the delegate count with Biden — much as he was at this point in 2016.

Plus, there’s a critical voting bloc that could help put him over the top: Hillary Clinton’s primary voters. As a 2016 Clinton delegate and a 2020 Bernie endorser, I have a simple message to voters who powered her winning campaign years ago: Come on over! The water’s fine.

I supported Clinton in 2016 for the same reasons many people did: After working with her for years and managing her 2000 Senate campaign, I’d seen firsthand her tenacity, extraordinary intellect and unrelenting drive to get things done. I know she would have been a great president — but it didn't happen, and, as Democrats, we need to understand that the mistakes we made then, we cannot afford to repeat now.

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Those of us who supported Clinton in 2016 and are working with Bernie now often hear three common misconceptions from voters to explain why they are considering Biden even if they like a lot of things about Bernie's positions.

For instance, we often hear some version of “I want someone who’s actually electable” — and we ask people to think about who’s really pushing the “Bernie’s too far left” narrative. It’s not real voters, but the establishment political class and pundits who worry they’ll lose their privileges and influence. It’s James Carville saying he's "scared to death" of Bernie and longtime members of Congress gossiping to CNN about his lack of institutional support.

Here’s the truth: Most of those people don’t understand how politics work anymore.

Today’s voters don’t care about newspaper endorsements or whom the party leaders most want to work with. They care about who will help them afford health care or take on climate change and they vote accordingly. So let’s listen to the people — the young and the Latino voters Bernie has inspired , the polls that show him beating Trump in Michigan, Wisconsin and Pennsylvania in the general election and the 56 of 60 national polls going back more than a year that show Bernie winning the general election. If you’re pragmatic about winning, vote for Bernie.

We also hear people say stuff like, “I want someone who gets things done,” because, for the past four years, the media has ignored decades of Bernie’s record. They’ve branded him as a stubborn, uncompromising outsider who puts ideology ahead of results. It’s an easy caricature — and it’s dead wrong.

In Burlington, Vermont, when he was elected mayor, he led a renaissance by working with people across the political spectrum and was voted one of the best mayors in America by U.S. News and World Report in 1987. And for 30 years in Congress, he’s been a reasonable, respected member . He reached across the aisle to work with Sen. John McCain, R-Ariz., to reform the Department of Veterans Affairs, and singlehandedly got $11 billion added to the Affordable Care Act for community health clinics in poor areas.

Bernie’s values will never change — and that’s a great thing. But he has shown over and over again he’s not naive about how government works. He’s gotten truly meaningful things done.

Finally, and most confusingly, we've heard people say, “I want someone with heart and empathy.” I understand the perception that Bernie can sometimes be a curmudgeon and I can’t lie — he’s guilty as charged. But there is also a deep warmth and humanity to both Bernie and his campaign. He connects with real people because he is real.

Watch his town halls and see for yourself how people who interact with him react with him. Really watch the next Bernie rally, including the speakers before him. There is a feeling of love in his campaign — a moral argument beyond policy that is unique in our politics. There is a beauty to how he speaks about the power of fighting for someone you don’t know. His campaign has tapped into a humanity in each of us, and that really matters.

And one more key point for a lot of Democrats reading: For decades, progressives in our party have come along for the ride when the party nominated a moderate. We worked our butts off for nominees who didn’t fully align with our own vision for the party and the country, because we knew that moderate Democrats were far better than Republican alternatives. Now it’s time for moderates to return the favor.

Bernie, not Biden, is the answer to the many of the mistakes we made as a party in 2016. He can reach the working class, inspire young voters and lead a powerful movement to take back the White House. It’s not too late to vote for him to be our party's nominee; this is not remotely over yet. Come join us and let’s get it right in 2020.

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