The Conservatives want the next election to be about Brexit and Boris Johnson in Number 10. Labour want the election to be about stopping no deal and issues other than Brexit like the NHS, education and the climate change crisis. In terms of how this plays out in marginal seats, both sides have headaches.
So let’s look at each of these points in turn. Firstly, Boris Johnson wants a gladiatorial contest against Jeremy Corbyn for control of Number 10. Johnson leads Corbyn by 40 to 20 per cent for best Prime Minister. In response Corbyn's allies cite the revival of his leadership numbers in the 2017 election; but hoping for an improvement in the numbers isn’t as good as having a strong position to begin with.
Next, the Conservatives want this election to be about completing Brexit, and want to contrast this with Corbyn’s potential for undermining or ending Brexit altogether. In August, by 48 per cent to 35 per cent (when forced to choose) voters opted for Prime Minister Johnson and no deal over Jeremy Corbyn and a second referendum.
Again, Labour needs to narrow the gap between these numbers if it wants to deny Boris Johnson an election victory. In terms of what Labour want the election to be about, the party will look to its 2017 success. For an election that was meant to be about Brexit, voters focused instead on topics that hurt the Conservatives like the so-called Granny Tax, the return of fox hunting and Theresa May shirking from debating Jeremy Corbyn. This was combined with a manifesto (that actually achieved the rare feat of making policy matter in an election campaign) that proved surprisingly popular with clear and direct left-appealing pledges, such as more money for public services, rail renationalisation and large-scale affordable home building.
Whilst strategists in both parties will want to make the election about their chosen issues, voters will ultimately determine what the 2019 General Election is really about. It may indeed prove to be the Brexit election that 2017 was not, or it may focus on traditional issues of leadership, or Labour spending vs Conservative tax cuts. But undervalued in all the strategic calculations, will be the power of events and the ability of voters to surprise Westminster with their choices in what matters to them in determining their vote.
In terms of the politics of Brexit, this is far from clear cut for Labour or the Conservatives. Indeed, Boris Johnson may have to be careful what he wishes for, if he wants to characterise Labour’s position as anti-Brexit. For what Corbyn needs most is to win back his 2017 Remain voters, who have worried for the last two years about his lack of clarity on Brexit. Corbyn's resolve in opposing no deal gives him a great opportunity to assert his anti-Brexit credentials in a way that probably does the least damage to the remains of the Labour Leaver vote.
On the other hand, Boris Johnson needs to not only unite his Leave vote, but prevent a mass-defection by Conservative Remainers to the Liberal Democrats. This means he should probably focus on asking: ‘who do you want in Number 10?’, rather than Brexit.
All of these factors will determine who wins the marginal seats that will decide the election. In this, Johnson starts from behind as he is likely to be down by perhaps 10 seats in Scotland, and 10-15 seats to the Liberal Democrats in the south of England. What’s more, with perhaps as many as a dozen of his now expelled ex-Tory MPs looking to stand in their own seats, he might face a further half-dozen rebel independent Conservatives in the new House of Commons. This seat maths makes life difficult for Johnson’s Conservatives. They will need to pick up perhaps as many as 30 seats from Labour in order just to make up for their losses. The Conservatives can likely look with confidence at 10-20 Labour gains, but 20-30, or even 30+, will be much harder.
Conservative strategists hope that returning Brexit party voters will aid them in this. But there may be a risk that many returning Brexit party supporters will live in existing Tory seats, rather than in marginals. In other words, the Tories may well be adding votes in the wrong places.
More important perhaps, is the potential role the Brexit party could play as a spoiler for Labour’s hopes of retaining seats. By running in Labour coastal and northern marginals, with larger concentrations of blue-collar Labour Leavers, the Brexit party could potentially draw down Labour majorities, allowing the Conservatives to come through the middle and win more marginal seats. This was in many ways, the main pro-Conservative strategic effect that Ukip had, hurting Labour and helping the Conservatives in the 2015 General Election. When combined with a Labour to Lib Dem Remainer defection of any significant size at all, the shape of the Conservative marginal seat strategy begins to take form.
To counter this, Labour will hope that the Tory toxic brand association that many Labour blue collar voters have long held will continue to hold sway. But whilst this may prevent outright defections of Labour Leavers to the Tories en masse, to prevent a loss of Labour Leavers to the Brexit party, Labour will hope that its anti-no deal position will not be interpreted by all voters in all places as a blanket anti-Brexit position. Labour will also try to draw on voters' traditional loyalty to the party, which was a key factor in Labour's dramatic 2017 poll uptick.
On the flip side, Labour must manage its Lib Dem Remainer defection risk. The ideal solution would clearly be a formal pact between the parties not to stand in those seats where the consequence of so doing would lead to a split in the Remainer vote and a likely Conservative victory. Failing that, Labour will hope that in its marginals, the Liberal Democrat candidates and campaigns will train their fire on the Conservatives, upping the number of Tory Remainer defections to the Lib Dems in a kind of mirroring of the role that the Tory Party hopes the Brexit party will play against Labour with its voters.
It is not just stating the obvious that Johnson needs to win big in this election. It is also essential. A 2.4 point victory for May in 2017, and even a 7.1 point victory for David Cameron over Gordon Brown in 2010, failed to deliver a Conservative majority. Johnson needs to achieve something closer to a double digit win for the Conservatives to retain more of both their Scottish and southern seats. As the polls currently stand, his best path to that is likely a presidential style contest between Boris Johnson and Jeremy Corbyn. Labour’s best counter will be to close the gap on leadership and to hope that the election is not dominated by the choice of Prime Minster alone.
Marcus A. Roberts is Director of International Politics at YouGov. He tweets as @marcusaroberts