The Republican presidential candidates will debate Donald Trump on Thursday night.

Yeah, I know. There’s 10 of them, and they are really debating each other. But there’s no denying it: Trump is the 800-pound gorilla in the room, and all he has to do is act like it’s an episode of "The Apprentice," and his polling numbers will go up 10 points. I'm not really kidding. People like that tough-talking, no-nonsense persona. They want to see him fire the media, the American political parties, big donors who think they can buy everyone and ISIS.

Granted, some of the candidates met in an oddly awkward forum on Monday, but Donald Trump wasn’t there, so what was the point of it anyway?

Who would have thought a year ago, or even six months ago, that Trump would be the guy to beat. At the moment anyway.

The media’s desire to paint Trump as a circus sideshow (Huffington Post even bizarrely relegated political news about him to the entertainment pages) has faded into the obvious reality: Donald Trump is the GOP frontrunner. Poll after poll have shown this, although it’s incredibly early. Every time he says something controversial, and the media bash him over it, it solidifies his standing with the considerable faction of conservatives who distrust the media, are disgusted by the political system as usual and want an outsider who will smash the status quo. Don’t underestimate how cynical people are about the political process.

Trump even gets center stage at this debate because he’s polling first. Which works to his advantage, by making him seem dominant and, thus, more presidential. Placement matters.

And so this debate is Trump’s to lose. The media have set the bar so low – convincing us all that Trump is crazy, running newspaper covers featuring him with a big red clown nose – that Trump’s mandate is simple: All he has to do is look plausibly presidential, stay in control and get off a few zingers or two to remind us he’s not like the rest of them.

This should be Trump’s stage. He’s used to television production, and this is just a big show. He’s adroit at playing to the cameras, and he’s mastered the art of the pithy soundbite that cuts to some essential truth (his Tweets are priceless), which is perfect for a debate forum where you don’t get much time to speak. Debates don’t allow for a lot of follow-up questions, so this keeps Trump firmly in control (where he likes to be).

The challenge for the other candidates will be to stand out amidst the pack and to deftly handle Trump. That means they have to, at all costs, not appear weak (if they lose their cool to him, they will seem weak). In one of the most recent presidential polls, the attribute that voters wanted more than anything else in a nominee was strength. They saw Trump as strong. This is not surprising. The world feels like it’s in chaos. ISIS is throwing people off roofs and beheading Americans on TV with virtual impunity. American cities have burned on television. The economy is still not where it should be. People want a strong leader this time, not one who breezily promises them hope. They want someone who promises them security. Trump reminds them of the carefree, affluent '80s.

So when Trump goes against the media or the political establishment – when he says WHATEVER HE WANTS – this connotes strength. The other candidates need to not crumple or flinch or erupt or ramble when he lobs a withering attack their way. At the same time, they need to not seem like unhinged attackers themselves and build him more. This will be quite a challenge. It's possible he will save his zingers for Hillary. This could work by making people think the rap on him has been unfair.

If I were advising the other candidates, I’d advise them that they need to start redefining Trump. One senses they’ve all been advised to let him implode on his own (but he’s not) and to avoid building him as a foil by attacking him (too late; he’s the clear frontrunner at this point). But if you investigate Trump’s past policy statements, they’re littered with landmines.

If Trump attacks Hillary in the debate, another candidate might toss out there, "Well, you know the opponent on my left once praised Hillary as ‘terrific,’ but my record contrasts clearly with Mrs. Clinton’s leadership failures," and then be specific. They might remind conservative voters that Trump once supported a wealth tax, that he’s supported aspects of gun control and that he used to be a Democrat – and then quickly pivot back to their own policy successes. Don’t talk about what Trump wants to talk about; talk about what THEY want to talk about and what Trump doesn’t want to talk about.

The problem is that Trump will have an answer for everything. He’s likely to retort something like, "A Democrat? Well, Ronald Reagan used to be one, too." So it’s tempting to advise the other candidates to pretend Trump is not there and to simply focus on making their own case to the public. The problem is, he’s probably going to be going after them, and if they don’t start educating people about his record, he’s going to remain defined as that tough talking "you’re fired" guy who doesn’t have to pander for money like the rest of them. Politics is a game of definition. I think they are making a huge mistake by not trying to define Trump now.

A few of the candidates didn’t make the stage. It’s unfortunate for Republicans that Carly Fiorina is among those. They could use a female in the mix to remind voters that the "war on women" doesn’t really exist. And she was impressive in the New Hampshire forum earlier in the week. Real vice presidential material.

I wish Rick Perry had made the cut too just because it would be enjoyable to pull up a picnic basket and watch Trump spar with him, and it would be entertaining to see if he showed up wearing the glasses Trump claims he wears to look smart.

So, here’s how I see each of the candidates who did make the cut.

Trump

In addition to looking plausibly presidential, Trump needs to make sure he doesn’t completely lose control. He needs to not say something truly nutty. Another Republican might trap him by raising the birther nonsense. While looking plausibly presidential (which means dominating the debate and staying in control), Trump needs to also retain the persona that makes him authentically Trump. He’s funny. He needs to stay the focus, not the sidelight. He needs to generate the headlines at the end of the day. And he needs people to think, "What was the media talking about? This guy isn’t crazy. I WANT this guy near the nuclear button."

Walker

Walker is good in these forums; he was good in the Monday forum. His biggest issue is that he says audacious things in debates that get him in trouble later when people fact check them or he doesn’t live up to them (such as saying there wasn’t really a shortfall or that he planned to serve another four years as governor).

The other problem is that Trump will be on the stage next to him, and Trump is not above fact-checking him on the spot. He will say the budget is balanced, and we have a surplus, ignoring the painful cuts and borrowing it took to get us there (which Trump might point out). The worst format for Walker is when he’s asked a series of follow-up questions in a tough one-on-one Chris Wallace style interview or when he’s asked about topics that he wants to triangulate on so as not to tick off either the media or the base.

Debates work for him though because he’s not likely to be asked a lot of follow-up questions, and Walker has his talking points down. Debates are usually full of softballs and niceties. This one might be different. They’re probably telling him not to respond to Trump. Or just to deflect anything Trump says by reminding people that Trump is helping Hillary. This could work, but he needs one simple rejoinder to Trump, no matter what Trump says. Something like, "Ronald Reagan wouldn’t appreciate the Republicans going after their own. Let’s keep the focus on Hillary. Here’s what I did in Wisconsin," and so on.

Walker’s central challenge will be to make sure he doesn’t tangle himself in a web of rhetorical knots, thereby reinforcing the disastrous early perception of himself as a flip flopper and obfuscator. If he looks weak and Trump looks strong and lands a few shots, if he doesn’t have an answer for Trump’s claims that "Wisconsin is a mess," Trump will cut even more into Walker’s standing as the "unintimidated" candidate.

Bush

Jeb needs to not fade away on the stage as Trump (and maybe Walker) suck the air out of the room. In the Monday forum, Jeb was underwhelming. He’s just not a strong presence. He came across as nervous, and he bobbled an easy question about his father and brother, rambling on too long and not making much sense. He seems cerebral and unlike his visceral brother (which isn’t necessarily bad if he self-edits and speaks with surety). He might let the others go at each other, so he looks like the "adult in the room." Don’t count Jeb out. He’s sitting on a ton of campaign cash. He just needs a clearer answer than he gave Monday on what he would do about his brother’s war.

Huckabee

Who cares? Not to be mean, but Huckabee will say a few avuncular comments that get a few chuckles. He will seem amiable. And no one will care. One wonders why some of these candidates stay in the race. Vanity? TV shows?

Cruz

Cruz sounded good in the Monday forum, and he will probably win a few points with conservative voters, especially with his strong stance on foreign policy. He will make more cautious candidates like Jeb seem weak, but his biggest challenge is seeming like he can win it.

Rubio

I think Rubio sounds and looks great, but he always comes across so young. He’s not that controversial, so Trump will probably ignore him, focusing instead on his nearest rivals Walker (and maybe Jeb). If Rubio looks and sounds great this time too, he solidifies his obvious chances at getting the VP nod, no matter who wins the nomination (although Fiorina would be great at that too).

Christie

Like Huckabee, Christie is a big personality. So he could have a great night, and dominate the debate, urging others to give him another look. But his charm hides an essential truth about the man: He’s kind of a Tony Soprano-esque bully. Of anyone, he has the best shot at landing a few blows on Trump. He needs to make sure he doesn’t blow his stack, though, or say something dumb (like raising the fact the moderator was implying he was washed up on Monday. Never give them a bad money quote like that).

Paul

Rand Paul hasn’t been getting much traction, probably because there are other "outsiders" entrancing conservative voters right now. The biggest challenge Paul faces, frankly, is not seeming so isolationist in a world with ISIS in it. How he handles foreign policy questions will matter. People are nervous about ISIS and the state of the world more right now than they are worrying about government collecting their phone numbers.

Kasich

The Ohio governor needs to not be boring and to find a way to stand out from that other Midwestern governor, Walker. He must differentiate. Otherwise, he just gets lost in the crowd.

Carson

The retired neurosurgeon is an impressive guy, and he might just be impressive enough that some people ask why they aren’t giving this guy more of a look?

Get out the popcorn. Monday’s forum resembled an awkward school assembly, with candidates watching each other from chairs in the front row, seeming bored. With Trump in the room this time, it should entertain. Too bad he won’t get to fire someone. Maybe, though, in a way, he will. As long as he doesn’t end up firing himself ...