Who would win a general election?

Anyone wondering why the Labour Party, consistently trailing about 10 points behind the Conservatives, sometimes seems so eager to have a general election need only be referred to the remark by Richard Burgon, the shadow justice secretary, during a routine knockabout on Sky’s Kay Burley breakfast. Reminded that his party was behind in the polls, Mr Burgon declared: “The polls said we wouldn’t win last time,” only to be sharply corrected by Ms Burley – “you didn’t”.

Indeed, speaking to Labour activists it seems that most of the wrong political lessons have been learnt from the admittedly impressive 2017 election performance, and that the lower Labour is polling, the higher the chance it will win a majority in the Commons. Some almost seem to believe that if Jeremy Corbyn managed to get his party down from its current dismal 25 per cent or so in the polls to what the pollsters call an asterisk rating (because an undetectably small level of support is represented by a * in their tables), then Labour would be set for a 1945-style landslide. It would certainly be a novelty.

As the master psephologist Professor Sir John Curtice dryly observes, then, “it’s not obvious that it should be wanting an election”.

At the same time, a snap election would also carry some risk for Boris Johnson, though he may fancy a gamble and feel he has little to lose. On balance, he might well win a small working majority – about the size of David Cameron’s in 2015 (12 seats overall). Still, in the middle-30s, his party’s poll rating is also a historically poor one for the Tory party, and his party has lost many a general election on that sort of showing. While Mr Corbyn is a little below Labour’s post-war low of 27.6 per cent at the 1983 election, Mr Johnson’s is barely more than John Major got (30.7 per cent) in their drubbing in 1997, the lowest poll by the Tories since the Great Reform Act of 1832. Everything is relative.

Things are made more unpredictable by the revival of the Liberal Democrats, the stonking showing for the Scottish National Party, an enlivened Plaid Cymru and Green Party, plus the continuing support shown for the Brexit Party. How each of these (not so) “minor” parties impact on the vote share of the (not much) bigger two, and how that is distributed across marginal seats, will also determine who gets to be the largest Commons party in an election.

As a working assumption, the SNP and Lib Dems will wipe out most of what is left of Labour and the Tories (post-Ruth Davidson) in Scotland. Across northern England, coastal communities, parts of suburbia and the Midlands, the Brexit Party might well carve out a chunk of votes from both Labour, in their usually safe seats, and the Conservatives, perhaps in less safe seats.

The chances of a big Brexit Party presence in parliament at the next election is low anyway, but if the country goes to the polls after 31 October and before Brexit, if “delivered”, then some polls suggest the Brexit Party would poll higher among disappointed Brexiteers than its current 12 per cent or so. It might even be sufficient to see the arrival of “Nigel Farage MP”; but the real impact of the Farageists will be on who out of Labour and the Tories the party hits hardest, and where. That is hard to judge.

As for the Lib Dems, they too will be looking to attract pro-Remain, pro-revoke and pro-second referendum supporters across the country, and will make the most progress in London, in university towns and the more prosperous parts of the country that voted heavily for Remain. Again, they may not return to their pre-coalition parliamentary strength, but will almost certainly make some gains (or re-gains) across the south, the richer parts of London and maybe their old heartlands in the southwest of England. Again how much they damage Labour and the Tories, and where, will be a factor in the result.

There may also be an unprecedented number of sitting independent candidates and former MPs switching parties and/or constituencies, such as ex-Streatham, ex-Labour, ex-Independent Group, now Liberal Democrat Chuka Umunna standing in Cities of London and Westminster – a big Remain stronghold. Some rebels may survive to play some role in the new parliament, and, in any case, would split the Tory/Labour vote in their old seats if they decide to run again.

The first wintry poll since 1974, possibly during a “Beast from the East” episode, also raises the issue of differential turnout. Will the voters who came out in the 2016 referendum for the first time in decades come out again for Brexit? And if so for which version – Johnson’s or Farage’s? Will the young this time register and back Labour – or the more Europhile Lib Dems? Will the Greens benefit from the recent climate controversies? Would informal pacts between parties make much difference?

First past the post is a peculiarly capricious electoral system. It is quite possible that the Tories will win the most votes, but have a lower reward in seats, and be the largest party in the Commons – but friendless. Thanks to their alienation of the DUP (whose stance should serve them well in their 10 seats), the Tories have no one to turn to sustain a minority government.

Labour, on the other hand, has the pick of parties it can cooperate with, though unlikely to form any formal coalitions. A Labour Party opposed to an economic border down the Irish Sea has more chance of winning the DUP’s acquiescence than Mr Johnson, after he let them down. A red-green-yellow-gold-orange coalition of the other parties, as now in the Brexit votes, could overwhelm Mr Johnson’s Tories (though, post-purge, they would be more reliably loyal to Mr Johnson and his Brexit deal).

Mr Corbyn, in other words, could poll far fewer votes but be on his way to see the Queen with just one in four voters behind him, the lowest “mandate” in British electoral history. The constitutional crises, in other words, may not be over.