James Frayne is Director of Public First and author of Meet the People, a guide to moving public opinion.

“Can they lead the Party to General Election victory?” This is the second most important question in the leadership debate. “How will they get us out of the EU by the end of October?” is top – and of course the two are linked.

Party members know they’ll be electing a Prime Minister who will be fighting another election in three years’ time, max. David Cameron beat David Davis in 2005 almost entirely because members put concerns about his ideological vacuity aside and decided he was a big electoral asset; this same contention would likely have propelled Theresa May into Number 10 against Andrea Leadsom in 2016. Members will be asking the same question this time, but the context is different, as the editor of this site explained yesterday.

Why can’t we just run some polls and watch some of Frank Luntz’s dial group jamborees on Newsnight (which so badly hurt Davis in 2005)? Because this time, the leadership candidates face an immediate conundrum. They absolutely have to give a commitment to leaving the EU by the end of October. If they don’t, they won’t win the members’ vote and they’d inherit a party on 20 points in the polls and heading further south. And committing to leave on this timetable requires convincing voters they really mean it – which in turn implies they’d have to publicly accept (how ever reluctantly) a No Deal exit. How, otherwise, could they absolutely guarantee Britain will leave? But most people don’t support a no deal exit – and it is hard to imagine them coming around to such a proposition. A decent chunk of legacy Leave voters are nervous about No Deal, as well as the overwhelming majority of legacy Remain voters. This all means the polls are going to be all over the place; success on Brexit for some voters, will be terrible failure for other voters.

We therefore need other measures of potential electoral attractiveness. I set out five big issues to consider here.

Firstly, members should be looking closely at how leadership candidates talk about No Deal. Those that rule out the possibility of No Deal entirely should be discarded as non-serious. Members and voters that have deserted the Party will simply stay with Nigel Farage and the Conservatives will have no viable electoral future; but those that embrace it enthusiastically should set off alarm bells because of how it will alienate those scared or repulsed by it. Candidates must present No Deal as an option they guarantee they will turn to – but only having exhausted other options and further negotiation. May’s experience is instructive here: initially, she persuaded voters she was serious about accepting No Deal and her numbers held up; over time, it became clear this wasn’t true and she was never forgiven.

This takes us to a second issue: how they talk about and deal with the EU. Eurosceptics like Nigel Farage have succeeded where no one else did before: they made the EU popular amongst a massive proportion of the British public. Before a referendum was called, almost nobody actually liked the EU; even five years ago it was impossible to imagine a physical march for the EU. Even pro-Europeans thought it was excessively bureaucratic, corrupt and undemocratic. But they thought it was necessary.

The referendum campaign, and above all its aftermath – dominated as it has been by Farage – has linked pro-Europeanism in many of the public’s mind with anti-extremism and anti-racism. Many legacy Remain voters now profess to love the EU because they fear the motives of Leave voters (wrongly, but that’s life). Leadership candidates have got to find a way of talking about the EU and its leaders with respect. They need to lay it on thick that, while the EU isn’t for us, they’re close allies that we’re committed to working with for our mutual defence and prosperity. They need to look as different from Farage as it’s possible to be.

Which takes us to a closely-related third issue: how they talk about immigration. The referendum was dominated by the question of immigration. While Vote Leave’s rhetoric and proposed policies were controlled, they still hit the issue hard in the final weeks (their ads were brutal on the issue) and this put many voters off. And, again, Farage’s stuff was occasionally appalling.

Leadership candidates must find a way of healing the wounds on this issue – forging a post-EU immigration policy that reflects new controls but is fundamentally liberal and highly encouraging of high-skilled migrants from across the world. This is where the public is in any case (as Open Europe’s research showed). The Party’s inability to grasp this point is strange. May’s obsession with numbers was in near total opposition to public opinion here. Boris Johnson has previously advocated a highly liberal immigration policy and Michael Gove has announced new policies which emphasise generosity. This is encouraging.

The fourth issue is how creative the candidates are in explaining how they’d use new freedoms available post-exit. From a campaign perspective, this was May’s biggest failing. She simply never articulated how things might be better outside the EU and, as others have described, she talked about Brexit entirely through the prism of risk mitigation. But practically no one else in Government talked persuasively about life outside the EU either. Serious candidates have to change this. We will never know how many voters the Government could have won over since 2016 had they created such a platform. (Anthony Browne has been addressing this over the last several days on this site).

The fifth issue is what they say about the Conservatives’ electoral priorities. As even occasional readers of this column will know, I believe the Party should create a campaigning and governing platform that prioritises working class and lower middle class voters in provincial England. I believe they should see the broad coalition of Leave voters as their new core. Because so few Conservative commentators ever meet ordinary people, and because many view provincial England with disdain, they assume that this means some sort of ultra-right-wing, hardcore traditional approach when it means nothing of the sort. Rather, it means improving public services, above all the NHS, ensuring work pays properly and certainly more than welfare, keeping taxes as low as possible and keeping the cost of living down, making it easier to buy a house, and keeping streets safe.

This is not to say that all candidates must accept these conclusions; they and others might strongly and rationally disagree with this approach and might indeed think that all of these columns are unsophisticated rubbish. The point is that we should expect candidates that want to portray themselves as potential winners should have a clear and reasoned electoral strategy. It isn’t enough simply to say we have to appeal to young people “because they’re our future”, or that we have to appeal to people in cities “because they’re growing”.

In summary, asking whether candidates can win demands they explain how they’d deliver Brexit in the least divisive way possible – and who they think the Party’s natural voters are. (For some more on this, check out George Trefgarne’s excellent piece on CapX and the editor’s excellent piece on this site).

There’s actually another issue to throw in at the end. Does the candidate seem ridiculous? There are some that are entering the campaign who, when their names are raised, provoke laughter (in a bad way). Members should ask around. If the candidate’s name makes people laugh (in a bad way) then it’s probably best not to vote for them.