I have plotted to win TV election debates. Ahead of tonight’s clash, here’s what Starmer and Sunak need to know | Giles Kenningham

In the wall of general election noise and multiple news cycles a day, TV debates provide the moment of maximum jeopardy. For many of the public, this first head-to-head may be the moment they start paying attention. For the leaders, it will be the culmination of hours locked in preparation, gaming out every scenario. Keir Starmer has everything to lose. Rishi Sunak has nothing to lose.

The debates have the potential to electrify the campaign. In US political history they have provided some defining moments. Ronald Reagan, the oldest sitting US president at the time, stole the show and shut down questions about his age during the 1984 presidential debate with his Democratic opponent, Walter Mondale, delivering the line: “I want you to know I will not make age an issue of this campaign. I am not going to exploit for political purposes my opponent’s youth and inexperience.” In 2010 Nick Clegg hit David Cameron and Gordon Brown with the zinger: “The more they attack each other the more they sound like one another.” And Cleggmania was born.

The obstacles and dynamics of navigating and winning debates in 2024 are much more complex in an age of social media minefields. The Tories have already landed the first blow, securing a two-way debate. For Labour this is a format faux pas. It should have argued for all the main political parties to take part. The Tories would have been a sitting target with a 14-year record to defend. It’s very hard for a clearcut winner to emerge in a seven-way debate, which can be unwieldy and descend into unseemly shouting matches – a perfect outcome for a Labour party with a commanding lead in the polls.

What happens in the days before the debate is as important as the night itself. What are the tests you set for the other side in the run-up? For the Conservatives it will be focusing on areas of perceived weakness for Labour – the economy and security. And for Labour it will be focusing on the NHS – an issue on which it always outpolls the Tories.

Labour has the added political headache of how, as the frontrunner, to play down expectations and take the heat out of the occasion. Arguably, Sunak has the advantage of being more match fit: not only does he already have a number of TV debates under his belt, having previously stood in for Boris Johnson in 2019, but also has clocked up the hours, having gone head-to-head with Liz Truss in ill-tempered exchanges during the 2022 Conservative leadership race. He has received in-depth briefings from the civil service on every subject imaginable over the past 18 months. Even the most well-resourced Labour party can’t compete with that.

So far, no defining or overarching message has emerged in this election. Both sides need to crystallise their pitch. Labour wants “change” but change of what? Expect the Tories to push the narrative that Starmer “stands for nothing” and press him on what his exact plan is for the country. Key for both sides is to be memorable where they have the advantage and boring where they want to be forgotten.

Starmer and Sunak are serious, sober and, some may argue, dull politicians. They are not political rock stars like Bill Clinton or Barack Obama. There is a danger of them cancelling each other out. Will a risk-averse Labour leader not known for his rhetorical flourishes deliver a memorable standout moment? Sunak will have to take more risks, so expect him to come out swinging.

People will consume the debate in many ways. Some will watch it by appointment, others in clips and instalments on Facebook, Twitter, TikTok and some on messaging apps such as WhatsApp. Politicians cannot forget to speak to both formats. If they merely debate using soundbites it will be car-crash TV. They have to answer properly in the moment and choose three or four lines to punch up for viral clip purposes.

And how do they convey empathy? Emotion will trump reason in the short window the politicians have to capture the public. Repeated use of case studies can look inauthentic. Use them but don’t overuse them. Both leaders will be well advised to dump the tired cliches. And avoid reeling off endless unrelatable facts.

It came to be a running joke in Conservative campaign headquarters during the 2015 election that Ed Miliband took a lectern everywhere with him as he tried to look like a prime minister in waiting. In a moment worthy of The Thick of It, he stood behind a lectern in a back garden in Wales. But in all seriousness, will you see either leader move away from the comfort blanket of the podium, take their jackets off and try to own the stage and emotionally connect with the audience? With multiple cameras covering every slight movement, twitch and hidden expression it may be what isn’t said that captures the night. One of the most famous moments of the 1992 presidential race was when George Bush Sr was fatally caught looking at his watch after a question about the national debt.

Crucially, both teams will need to spin the outcome well before the credits have started rolling. And both sides will have thought carefully about who the big beasts of their respective parties are who they want spinning the result after the debate ends.

Ultimately, the success of the night will depend on a robust moderator who can call out any Donald Trump/Boris Johnson-style filibustering and factcheck in real time. The 2010 election was the last time that televised debates drove the narrative and affected the outcome. Labour wants a forgettable night. The Tories need to electrify this election and change the conversation. They will throw the kitchen sink at it. How can you judge who wins? Watch out for who dumps the proverbial dead cat (handy diversion) on the table the next day.