Editor’s Note: Sally Kohn is an activist, columnist and television commentator, and a supporter of Bernie Sanders. Follow her on Twitter: @sallykohn. The opinions expressed in this commentary are solely those of the author.

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Sally Kohn, a Bernie Sanders supporter, says he has lost primary race to Hillary Clinton

She says Sanders must turn discontent into action -- a revolution to defeat Donald Trump

CNN  — 

On March 31, 1973, when Muhammad Ali stepped into a boxing ring in San Diego, he was wearing a robe given to him by Elvis Presley and he was favored 5-1 to beat Ken Norton, who was then rated No. 6 in the world. But after 12 rounds, Ali had a broken jaw and Norton won the split decision.

After the defeat, only the second in his career, Ali said, “I never thought of losing, but now that it’s happened, the only thing is to do it right. That’s my obligation to all the people who believe in me. We all have to take defeats in life.”

Bernie Sanders, listen to Muhammad Ali.

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In California, Sanders supporters not giving up
02:09 - Source: CNN

The Democratic primary is over. Hillary Clinton has secured the 2,383 delegates required to win her party’s presidential nomination – amassing both more pledged delegates and superdelegates than Sanders.

It was unfortunate that the AP decided to call the race before states like California and New Jersey weighed in, but even those votes are just to confirm the now foregone conclusion. Say what you will about the primary rules and whether they should be reconsidered, Hillary Clinton played by those rules and won fair and square. And Bernie Sanders lost. The only thing left now is for Sanders “to do it right.”

I still believe in Bernie Sanders. I believe in his commitment to make the Democratic Party more accountable to progressive populist values and to make American elections more accountable to voters. That has been his revolutionary mission from day one – to disentangle our political system from Wall Street and big business and thus render the decisions and actions of politics less reflexively centrist.

And Sanders has already succeeded. Clinton is a more progressive and accountable candidate because of Sanders. Her positions on fracking, universal health care and the Trans-Pacific Partnership trade deal have all become more progressive because of Sanders’ prodding.

That’s good for Democrats and for Clinton. On the one hand, with Sanders out of contention, more progressive positions will help Clinton animate the Democratic base in the general election. And faced with Donald Trump, whose candidacy has in no small part been fueled by his anti-trade tirades, Clinton is in a stronger position to appeal to swing voters on this key populist issue.

Plus Sanders has made Clinton a better candidate in terms of style as well as substance. In debates and on the stump, Clinton has genuinely gotten better at being relaxed as well as at sharpening her points. Having a challenger forced her to raise her game for black and Latino voters, who likely otherwise would have been taken for granted as they usually are by the Democratic establishment.

Though I wish it had been even more pronounced than a few questions about “voters of color” during the Sanders-Clinton debates, it was still a noticeable and welcome change that we were discussing this at all, largely due to the unrelenting and important leadership of Black Lives Matter and pro-immigrant rights advocacy groups.

The longer-term work of the Sanders revolution remains unfinished, however. The Democratic Party still must grapple with how it reflects the broader populist moment sweeping the Democratic base and the entire country. Voters on both sides of the aisle are clearly fed up with politics as it is – and understandably so.

FAIRFIELD, CA - JUNE 03: Democratic presidential candidate, U.S. Sen. Bernie Sanders (D-VT) speaks during a campaign rally at Cloverdale Municipal Airport on June 3, 2016 in Cloverdale, California. Five States including California will hold the final Super Tuesday primaries next week. (Photo by Ramin Talaie/Getty Images)
What the end of the Sanders primary campaign looks like
02:07 - Source: CNN

And Sanders remains uniquely positioned not only to crystalize that discontent but turn it into constructive action. So his supporters weren’t able to win the primary race. They can still win the sort of vital structural reforms that will make politics more representative and accountable going forward. Sanders must continue to lead this fight.

What he must not do is continue to fight Clinton.

Instead he must enthusiastically and energetically support the Democratic Party nominee and urge all of his supporters to do the same. At the same point in 2008, large percentages of Clinton supporters said they wouldn’t vote for Barack Obama if he became the Democratic nominee and many said they would support Republican John McCain instead, but those Clinton supporters eventually came around, in no small part because Clinton herself vociferously encouraged them to do so.

Sanders and his supporters, myself included, have key differences with Clinton, and those differences won’t go away. But they are undeniably dwarfed by the massive departure from core values and the lack of basic experience and competence that Trump represents. It’s time for those who have even deep concerns about Clinton to come to their senses.

Bernie Sanders and Hillary Clinton agree on far, far more than they disagree. And we must not allow Trump to become president.

The Sanders revolution can and should continue on to the Democratic National Convention and beyond. But the Sanders campaign, in any formal sense of trying to win or wrest the nomination, should end.

The sting like a bee phase of this primary is over. It is now time for Sanders and his supporters to float magnanimously like butterflies – to champion Hillary Clinton and defeat Donald Trump.

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Sally Kohn is an activist, columnist and television commentator, and a supporter of Bernie Sanders. Follow her on Twitter: @sallykohn. The opinions expressed in this commentary are solely those of the author.