For Trump and Clinton, this second debate could be kryptonite

The second presidential debate, coming up on Sunday night, will be town-hall style and that could be kryptonite for both Donald Trump and Hillary Clinton.

What Trumps supporters often say they love about him is his brash, often politically incorrect, and even boastful speaking style that resonates. A lot of Clinton's truest supporters say they love the way she speaks with the authority and self-assured tone of a long-serving and knowledgeable politician.

Those characteristics may work well in a forum full of supporters but they could easily derail the candidates at Sunday night's upcoming town hall format debate. In fact, if they both don't noticeably deviate from their signature styles at this forum, they could both easily face instant disaster in the polls.

Of course, it's important to note that the decidedly anti-democratic and barely accountable Commission on Presidential Debates keeps these town-hall affairs from being a real exchange between random voters and the candidates. Follow-up questions were banned in 1996 and the commission pre-selects the audience and pre-screens the questions. This is what you get when the establishment in both major parties takes control of the process. Only in Washington would a commission stacked with an equal number of highly partisan Democrats and Republicans get away with call itself "non-partisan."

But in this era of canned rallies and campaigning via Twitter, this is about as organic as it gets.

And there's the danger for both Trump and Clinton.

In front of those raucous Trump rallies, the Republican nominee thrives with his boasts and tough talk. He speaks provocatively about his political opponents, the media, and even the protesters spread out through the crowd. For a candidate looking to project strength and connect with angrier and long-ignored white working class male voters, this is a formula that works. But transfer these ingredients to the town hall format with a crowd that can't applaud, can't holler approvals, and instead is looking for some personal attention from him.

If Trump is asked a challenging question by a voter Sunday night and he answers with an angry brushoff, his supporters watching at home may like it, but it will kill him in the room and among lots of supposedly undecided voters. At the same time, if he totally changes his persona to an inauthentic-sounding sensitive guy that might turn everyone off. Trump has to thread the needle by sounding concerned and/or angry about the economy, terrorism, and immigration without sounding angry at the person asking him the question. This will be particularly difficult if an immigrant or Muslim voter is one of his questioners, something that's a good possibility.

The good news for Trump is that, while he's not a politician, he's very used to this general kind of format. He reportedly hasn't done much prep for this debate, but he's done live studio audience interviews and shows for more than 30 years from the Oprah Winfrey Show to numerous sparring sessions with Howard Stern and his callers on Stern's radio program. Still, this won't be an easy transition from his combative style on the campaign trail and in the first debate. He might want to reconsider just "winging it" again if those reports are true.

Meawhile, for all Hillary Clinton's supposed advantages, she is the one who may have a steeper hill to climb in order to strike just the right tone in this second debate. Anyone who saw her performance at the quasi-town hall format during NBC's Commander-in-Chief forum last month knows it. When asked about her email scandal, another question that seems extremely likely to be asked again Sunday night, Clinton seemed more than a little perturbed. The self-satisfied smiling little shimmy she did after Trump went on one of his longer rants at the first debate would also be a poisonous gesture for her at any time in this different forum. Her campaign staff is going to have to work on getting her to change that tone and her facial expressions this time.

On other issues and questions, Clinton has to make sure she doesn't sound too superior while trying to explain complex policy positions to the real, live voter in front of her. That kind of impatience or annoyance was something many voters saw in President George H.W. Bush in his town hall debate performance against Bill Clinton and Ross Perot in 1992. Considering how much the news media and the other pundits pounded Bush's inability to connect personally with a voter who asked about the human effects of the national debt and his supposedly fatal decision to check his watch during another moment in that debate, Hillary Clinton should be the last person to forget just how damaging a disconnected comment or even brief look could be.

And Clinton's made those looks and used the wrong tone a number of times over the past two years. Her recent angry-toned, "why aren't I up by 50 points you might ask?!?" comment has already been turned into an instant campaign ad by the Trump team. Her frustrated, "what difference does it make?!?" response at the congressional hearing on the Benghazi attacks would be another example of something she absolutely cannot do in this debate. That's even though her supporters cheered that response from afar as an example of Clinton's toughness in the face of what they continue to see as a partisan witch hunt. Remember, what works for the base can really fall flat in a more neutral setting.

Is there an antidote for the debate kryptonite for both these candidates? There is when you remember exactly how Bill Clinton out-shined Bush and Perot in that 1992 town hall. Instead of just trying to personally connect with the national debt questioner with his own words, Clinton is the one who asked a follow up question to her. Nothing shows people that you're willing to listen or try to connect with someone more than letting them speak more. It's a good trick used by the most persuasive candidates and salespeople, and it's one Bill Clinton had in abundance. Hillary Clinton hasn't shown that she does so far and we don't really know if Trump can do it either. Watch closely to see if any of the candidates solicits more information from the voters at the town hall, and how often and well they pull it off.

If Trump can't find some way to connect with at least some of his questioners Sunday night in a likeable way, he's going to have a long night. But if he can, it could be a transformative moment just over four weeks before Election Day. For Clinton, this is the time when her more polished and professional campaign could hit a serious snag. If she can't respond to questioners in a way that doesn't seem scripted or too rehearsed, she risks losing the momentum she gained from winning the first debate and could also lose it all. And as Mitt Romney found out the hard way in 2012, you want to win the second debate, not so much the first.

The stage is set, and so are the traps. Which candidate will be able to tip-toe around them or even take a serious new advantage right during the election's home stretch?

Commentary by Jake Novak, senior columnist. Follow him on Twitter @jakejakeny.

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