It’s possible, of course, that the candidates will refuse to accept the premise. After all, an NBC/Wall Street Journal poll last month showed 85 percent of Democrats actually are very or somewhat satisfied with the candidate field.

Make no mistake, however, this imaginary debate questioner is not really a figment of imagination. More like a composite of real people in the Washington political class who generate skeptical static in phone calls and emails and lunches with other operatives and with journalists who write stories like this one.

The suckage factor is the unmistakable context of tonight’s Democratic debate in Atlanta. All the candidates, to one degree or another, are laboring with a hovering perception among Democratic influentials that, for one reason or another, their candidacies are suffering from fundamental infirmities.

That perception is what has tempted latecomers to barge in—Michael Bloomberg and Deval Patrick, neither of whom will be on the stage—and has even aroused speculation about the intentions of former nominees John Kerry and Hillary Rodham Clinton. Former president Barack Obama, who often says he disdains “cable chatter,” weighed in the other day with a warning to candidates to not confuse “left-leaning twitter feeds” with the views of most voters, who “don’t want to see crazy stuff.”

The 2020 Democrats can comfort themselves with the knowledge that every nominee in both parties for at least the last 40 years has experienced some period of hazing, in which the professional political class was consumed with discussion about their perceived electoral defects. (Of course, for half of those people the doubts were arguably proven correct in the end.)

For now, each of the debaters at the MSNBC/Washington Post debate all face variations of the same increasingly urgent challenge—tell us why you don’t suck, or admit that you do but explain why it doesn’t matter as much as many people assume. Thanks to my colleagues Marc Caputo, Chris Cadelago, Holly Otterbein, Elena Schneider, and Alex Thompson for their help in framing how the candidates are defining success tonight.

Elizabeth Warren: End the Medicare for All obsession

Thompson notes a paradox. In Warren’s stump, Medicare for All usually comes up peripherally or not at all. The subjects that clearly animate her most are bringing corporate power to heel, tilting the tax code to help working people and making the very wealthy pay more, and programs like canceling student debt and universal health care. And yet: Medicare for All, and Warren’s staccato explanations of her own position, have dominated the narrative for a punishing stretch of her campaign. Other candidates pressed her hard at last month’s Ohio debate on how she would pay for it. And among the professional class there is widespread concern that an impressive but unseasoned presidential candidate allowed herself to be boxed into a corner—with a position so toxic it could be fatal in the general election.

Warren’s task Thursday is to convince two distinct sets of people that she’s solved the problem. For average Democratic voters, Warren can point to a recent burst of detail about how she would stitch together various savings and new revenue streams from companies and high-earners to pay for her plan with “not one penny in middle-class tax increases,” as she put it in a Medium post. The plan is complex but the message is simple: I got this.

For those in the Democratic professional class, who worry about the general election, Warren can talk about another plan, laying out her priorities once winning office (Medicare for All isn’t in the top three) and how there would be a transition plan of several years before the elimination of private insurance plan. The message: This is all foggy and speculative enough that voters will realize they don’t need to freak out over details that will probably never happen or conclude that I’m a dangerous radical.

Success for Warren at this debate would be to parry questions with such detail that everyone—opponents, reporters, Obama—cries “Uncle” and moves on.

Pete Buttigieg: Time to get serious, young man

The South Bend mayor is well-aware that he arrives with a target on his back unlike any previous debates. That’s due to this past weekend’s Des Moines Register/CNN/Mediacom poll, showing him atop the field in the Iowa caucuses.

This will have Buttigieg likely being the target of criticism in ways he has not at previous debates. On those occasions, he has scored points for sounding articulate and sensible beyond his years—something he no doubt learned he can pull off in kindergarten—but he also tended to move in and out of the conversation, never the central figure across the length of the evening. Many in that dreaded professional class still are not convinced that a 37-year-old small-city mayor can be taken seriously for the presidency. In fairness, probably many average voters will be watching through the same prism.

Buttigieg also must look for opportunities to address and begin reversing his notably low support from African-Americans.

Schneider notes that it is likely he will emphasize his plans on health care and college affordability, two areas where he has the clearest differences with Warren and Bernie Sanders and where his positions are much more attuned with Obama’s plea that the “average American doesn’t think we have to completely tear down the system and remake it.”

Joe Biden: C’mon, man, I’m not that bad

The former vice president turns 77 today. It is unlikely he will celebrate with a bravura debate performance.

After four previous debates of sentence fragments, baffling or cringe-worthy non sequiturs or anachronistic lines (such as in the third debate when he said parents should “have the record player on at night” to teach kids new words), there surely are few Americans who plan to vote for him because they think he is a superb debater. It is more reasonable to assume that anyone who doesn’t want Biden because they think he is inarticulate on stage has already switched his or her allegiance to another candidate.

If it’s not likely Biden will dazzle in Atlanta he could still benefit from a strong and steady outing. One result would be to cause the political-media class—which often speaks about his candidacy as though it were terminally ill, in large part because he is not currently poised to win Iowa or New Hampshire—to look through the other end of the telescope. Even with a year of publicity questioning, among other topics, whether he makes women uncomfortable by being too familiar, whether he is showing his age, whether his family’s business dealings are a problem, he remains atop most national polls. He needs the focus to remain on that if he does indeed underperform in Iowa and New Hampshire in early February.

“Joe knows he doesn’t have to be the best on stage. He needs to be good enough,” a fundraiser and friend who has discussed debate strategy with Biden told Caputo. “The reality is the media makes a lot more of these debates than voters do. And it’s not like they’re real debates about policy. These are TV shows.”

Bernie Sanders: Show some heart

In one sense, appraising the Vermont senator’s debate performances is easy. A good one is little different than a bad—none vary much in message or tone—and people either like them or they don’t.

As POLITICO’s Holly Otterbein noted recently, Sanders’s recent cardiac arrest actually seemed to give his campaign a boost.

Still, there aren’t many people in the chattering class who chatter seriously about the prospect of Sanders being the nominee—despite his durable coterie of support and how close he came to beating Hillary Clinton for the nomination in 2016. He must walk a balance, distinguishing himself from Warren without shredding their non-aggression pact and potentially angering her backers. He must stand out enough that he can’t be ignored in the media coverage.

A winning night in Atlanta might offer something slightly different— more humor, more personal insight, an anecdote about a tunnel filled with light? Anything: Surprise us—that suggests Sanders can present himself in ways that widen his support beyond his loyal base and he has prospects not just to influence the race but win it.

The rest: There is still (a little) time

The balance of candidates may be residing in the second tier, but even that is a somewhat impressive feat. The Democratic National Committee’s tightening eligibility criteria has already shooed numerous other candidates off the stage.

At a minimum, these people should enjoy their remaining time in the spotlight. At best, there may be some openings to add to the top tier or kick someone else out of it.

That’s what Minnesota Sen. Amy Klobuchar is hoping to do, with a repeat of a widely praised debate outing last month. She hopes to demonstrate that she may have less novelty than Buttigieg but more credibility, having won previously in an important Midwestern state, and therefore is the natural beneficiary for people who think Warren and Sanders are too liberal and that Biden is unimpressive.

There is not yet much evidence that 2020 is the year for Sens. Cory Booker or Kamala Harris. It’s not that they necessarily suck—they just so far have not mattered. Both arrived in the race with strong reputations as ascendant politicians, but neither has exceeded (or arguably even matched) expectations of the political-media class. Both have had some eye-catching moments in previous debates that they failed to turn into forward momentum in polls. Both need performances that remind people why they have those reputations in the first place. This could cause lightening finally to strike, or at least keep them in contention as vice presidential prospects.

If our imaginary consultant got to decide, it’s likely that Rep. Tulsi Gabbard, tech entrepreneur Andrew Yang, or hedge fund billionaire and impeachment advocate Tom Steyer wouldn’t be on the stage. These people don’t interest him at all.

Fortunately, consultants and reporters don’t really get to decide. All three candidates in their own ways have enlivened previous debates, have some committed supporters—lots of them in Yang’s case—and have another opportunity to steer the debate in unconventional directions that it wouldn’t go if their voices were unheard.