Editor’s Note: Paul Begala, a Democratic strategist and CNN political commentator, was a political consultant for Bill Clinton’s presidential campaign in 1992 and was counselor to Clinton in the White House. He is a consultant to the pro-Hillary Clinton super PAC Priorities USA Action. The opinions expressed in this commentary are solely those of the author.

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Paul Begala: Some are pressing Bernie Sanders to quit and leave field to Clinton. Don't do it, Bernie

Begala: Sanders should stay in, show world how to dismantle the phony, bigoted, plutocrat: Trump

CNN  — 

Dear Bernie:

Don’t drop out of the race; redefine it.

As you know, I am a friend of Hillary Clinton’s. I also advise a super PAC that helped re-elect President Obama and now supports Hillary. But I also have known, liked, respected and admired you for many years, and you know that, too.

We shared the stage at the 2011 Tom Harkin Steak Fry in Iowa, and I cheered as you lit the crowd on fire that soggy afternoon. You seemed to like my barbs aimed at the GOP, too.

I recall two decades ago, when you and Hillary were both fighting for universal health coverage – back when it was called Hillarycare – you hosted the first lady on a trip to Vermont and I tagged along. I still remember how gracious you were – and how good the ice cream was.

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Bernie Sanders' entire Indiana victory speech
11:19 - Source: CNN

Despite my devotion to Hillary I do not think you ought to withdraw from the race, and it is wrongheaded for anyone on my side of the Democratic contest to presume to tell you to. To quit or not to quit; that is not the question. The question is: Will you use your campaign to show Donald Trump how to attack Hillary – or to show Hillary how to attack Donald Trump?

Now that the GOP field has cleared for Trump, you can guarantee he will focus all his hateful, bitter vitriol on Hillary. If you continue to hammer her as well, she will be in the difficult position of receiving friendly fire from you, even as Trump is launching chemical weapons at her. You are in a uniquely powerful position. You can either force Hillary to fight a two-front war, or force Trump to. I am urging you to choose Trump as your target.

He is a tailor-made villain: entitled, arrogant, obnoxious, with a message of xenophobia, misogyny and division. He is a plutocrat who inherited millions and has the cojones (in Brooklyn I gather they call it chutzpah) to masquerade as a populist. The kind of guy our mutual friend, the great Texas populist Jim Hightower, says “was born on third base and thought he hit a triple.”

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Will Clinton and Sanders cut a deal on platform?
06:34 - Source: CNN

You have done great service to your movement by shining an unblinking spotlight on income inequality, campaign finance reform and economic justice. But something happens in the course of a campaign – I’ve seen it many times. The focus can shift from the cause to the fight; from the issues to the attacks. Prodded by campaign consultants like me, candidates often abandon righteous indignation at a system stacked against working folks for bitter, sarcastic, personal attacks on their opponent.

But Hillary, while doubtless more moderate and pragmatic than you, is simply not the personification of what’s wrong with the system – and you’ve said as much yourself. You have spoken of your respect, even admiration, for Hillary. “Maybe I shouldn’t say this,” you’ve said. “But I like Hillary Clinton.” And I know she has the same high regard for you.

You rocketed from obscurity to global fame by focusing on issues, not insults. In fact, your campaign stalled when you went into attack mode. I doubt Pope Francis asked you to attend a Vatican conference on building a moral economy because of a snarky soundbite attacking Hillary for giving paid speeches.

The hard truth is the math makes your winning the Democratic nomination impossible. Hillary has won more votes, more states, more pledged delegates and more superdelegates. But you have a chance to win something nearly as important: the ability to shape the debate. Sure, that will take the form of trying to massage the Democratic Party’s already progressive platform (which many will debate ad nauseam, then no one will read).

I am talking about a more powerful platform, leveraging a more potent vehicle to draw attention to your issues: the saturation media coverage of Donald Trump. In a masterstroke of jujitsu, you can use the power of the free press Trump attracts to highlight all the ways you think he’d be a disaster.

Show the world – including Hillary – how to dismantle Trump: his inherited wealth, his made-in-China ties, his belief that wages are too high, his plan to cut taxes for the billionaire class, his phony-baloney Trump University, his four business bankruptcies, his breathtaking cynicism in pretending to be an outsider while a Washington lobbyist pulls the strings of his campaign.

And that’s before you even turn to his deranged attacks on Mexicans, Muslims, women, the disabled, POWs and more.

The cause of your life has been economic justice. I cannot imagine anyone who would do more damage to that cause than Donald Trump. As you carry your campaign forward, I hope you will consider George Santayana’s observation that fanaticism consists of redoubling your efforts after you’ve forgotten your aims.

Your aim has always been true: a more decent, just, compassionate, equitable America. From this day forward, attacking Hillary serves only to diminish that aim. But turning your considerable firepower on Trump can ensure that you win something far more enduring even than four years in the White House.

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Paul Begala, a Democratic strategist and CNN political commentator, was a political consultant for Bill Clinton’s presidential campaign in 1992 and was counselor to Clinton in the White House. He is a consultant to the pro-Hillary Clinton super PAC Priorities USA Action. The opinions expressed in this commentary are solely those of the author.