Editor’s Note: David Axelrod, a senior CNN political commentator and host of “The Axe Files,” was senior adviser to President Barack Obama and chief strategist for the 2008 and 2012 Obama presidential campaigns. The opinions expressed in this commentary are his. View more opinion articles on CNN.

CNN  — 

I can imagine two reactions at Biden headquarters Thursdsay night when the lineups for the CNN debates in Detroit were drawn.

The first is that this is a potential disaster. Flanked on the July 31 stage by two of his most aggressive attackers and several feisty progressives, who are desperate for a big moment to keep their bids alive, the former Vice President could find himself a frequent target.

But, as my middle school basketball coach always said, every challenge is an opportunity.

The front runner in polls, Joe Biden, who faltered in the first round of Democratic debates in June, will have a chance to soothe his anxious supporters by confidently swatting down the incoming and proving that, at age 76, he’s still got game.

The second night

One consequence of the random draw is that Biden, who has struggled on questions of race, will find himself competing on the second night of back-to-back debates on a stage that includes every candidate of color in the Democratic field.

Standing to the left of Biden will be Senator Kamala Harris of California. Her riveting, made-for-TV takedown of the former VP in Miami over his opposition to mandatory school busing in the ’70s was the iconic moment of the last debate.

On Biden’s right will be Senator Cory Booker of New Jersey, who led the charge for a public apology after Biden boasted at a fundraiser of his working relationship in the 1970s with two of the Senate’s most virulent segregationists. Booker, who eventually got the apology, has failed to get much lift and will be looking for a big moment in this debate to ignite his campaign the way Harris did last time.

So, too, will the candidates who will fill out the stage, including two flamboyant New Yorkers, Senator Kirsten Gillibrand and Mayor Bill de Blasio, who are in danger of failing to make the cut for the next Democratic debate in September if they don’t dramatically lift their poll numbers from the land of one percenters where they current languish.

In September, the eligibility requirements to qualify for future debates will double, meaning candidates will be required to post at least 2 percent in four national polls between June 28 and August 28 and show 130,000 unique donors to their campaigns. To have any hope of getting there, Gillibrand and de Blasio – who made a lot of noise in the last debate but little progress – will need to break through in some dramatic way.

And, as Harris has proven, there is no better way to achieve that than a face-off with the front runner.

Gillibrand, who has staked her campaign on her leadership on issues such as sexual assault, could achieve that by challenging Biden over his long ago treatment of Anita Hill at the Supreme Court confirmation hearings of Clarence Thomas.

De Blasio, who got in late and is improbably hoping to muscle into a race already populated by several iconic candidates of the Left – Senators Bernie Sanders of Vermont and Elizabeth Warren of Massachusetts – was fairly hyperventilating in the first debate, breaking in whenever he could. Look for him to create a moment with the moderate former VP on ideological grounds.

Biden’s heat also will include Julian Castro, the former HUD secretary and San Antonio mayor, who drew notice in the June debates for his muscular confrontation with his fellow Texan, Beto O’Rourke, over decriminalizing the border. He will be looking for another such moment, perhaps with Harris, who now is polling in the upper echelon of candidates and has vulnerabilities with the left over her record as a prosecutor.

But Biden, who is blessed and cursed to sit atop the polls, should look forward to the honor of being a target throughout.

For unknown reasons, Biden was caught flat-footed by Harris in the first debate, giving rise to new questions about his age and stamina. (I still don’t understand why Biden didn’t play his strongest card when Harris challenged him, which is his partnership with the nation’s first black president – “Kamala, Barack Obama examined every aspect of my record and chose me to be his Vice President. That should tell you all you need to know about my record and commitment on civil rights.”)

Biden also could fairly turn on Harris for appearing the day after the last debate to walk back her position on busing to something that sounded a lot like Biden’s voluntary-not-compulsory position. And he might challenge her on her on-again, off-again support of Sanders’ plan to replace the entire private health insurance system under Medicare for All.

If the front runner who appears on the stage in Detroit is strong, agile and confident in handling the incoming – and unapologetically claims the mantle as moderate – he could take a big step toward solidifying his status at the top of his pack. If not, the lamentations about his ability to go the distance will grow louder.

Harris vaulted to the top tier in polling after her last debate. The upcoming the debate offers a chance to go beyond her moment and deliver a clear message, something she has yet to do.

If you believe, as I do, that the ultimate argument against President Trump is that his gleeful, nasty and unremitting penchant to divide the country is a dispiriting and exhausting barrier to progress, the charismatic Harris could emerge as a force to heal the breach. But that would require her to commit to such a message.

The first night

By the luck of the draw, Sanders and Warren will stand side-by-side on the July 30th stage – the first of the two CNN debates – surrounded by an array of moderates.

The two, who publicly profess their undying friendship, are locked in a fierce and bitter struggle for many of the same voters. Will all those expressions of comity fall by the wayside when the meet onstage in Detroit?

Their presence also makes them potential targets for the more moderate candidates on the platform. Mayor Pete Buttigieg of South Bend, the surprising early season phenom and fundraising champion, has the most to gain by carving out that turf.

Buttigieg, a 37-year-old, gay, Afghanistan War veteran, has impressed with his fluent New Generation appeal. He will be standing to the right of Sanders, who is 77, and that’s an image the younger candidate probably relishes. But his poll numbers have plateaued in the single digits and he now needs to flesh out his compelling rhetoric with deeper insight into what his new ideas campaign is about.

Buttigieg could be one candidate who challenges Sanders and Warren on health care, positioning himself as a pragmatic progressive from the center of the country – not far from Iowa, where the whole dance begins in February.

Senator Amy Klobuchar of Minnesota, whose whole campaign has been staked on Midwestern moderation, was on the platform with Warren in the first debate and failed to engage her. If Klobuchar is going to go anywhere in this race, warm and funny will not be enough. She will have another chance in Detroit to aggressively challenge Sanders and Warren over the issue of where Democrats should stand on health care, immigration and other defining issues.

O’Rourke, who will be flanking Warren, began the year as a bona fide top tier candidate but has underperformed expectations and badly needs a reset. He was more apparition than contender on the first debate stage in June, wilting under Castro’s immigration attack and retreating to a corner where he remained, almost silent, for the rest of the debate.

O’Rourke could make steak out of hamburger, seeking moderate turf by explaining why he, almost alone among the field, would not change the law to make border crossing a civil rather than misdemeanor criminal offense. Many, including me, viewed the headlong match to decriminalization in the last debate to be a gift to President Trump, who already has announced his strategy to portray Democrats as the party of “open borders.”

Or O’Rourke, who has made criminal justice reform a hallmark issue, could challenge Buttigieg from the left for his record in South Bend, where a recent police-involved shooting has raised questions about the mayor’s leadership on police-community relations.

There will, of course, be other moderates on the stage. Governor Steve Bullock of Montana, former Governor John Hickenlooper of Colorado and Rep. Tim Ryan of Ohio are closer to elimination than nomination and also may use Sanders and Warren as foils to create a campaign-saving moment.

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    But however it plays out, the debate cards produced by The Draw provide two vastly different lineups and a host of possible scenarios for events that could have dramatic implications for the future.