The Tories will do badly in today's local elections. So can Theresa May survive?

For the prime minister, and for Brandon Lewis, the priority is damage limitation

Polls opened at 7am in most of England outside London and in Northern Ireland. By the time they close at 10pm a large part of the electorate will have had its chance to use its democratic power.

The immediate issues today, according to Brandon Lewis, the Conservative Party chair, are “council tax, potholes and bin collection”. That’s what he wants to focus on, rather than Brexit. But everyone knows that the elections will be affected by national politics and will be interpreted as delivering a verdict on the government’s failure to get Britain out of the EU.

It will be a somewhat muffled verdict, however. Neither Nigel Farage’s Brexit Party nor Change UK, the pro-EU party founded by Labour and Tory defectors, was formed in time to run candidates in these elections. They wait their chance in the European Parliament elections in three weeks’ time.

Heidi Allen, the former Tory MP who is interim leader of Change UK, said the party “isn’t standing in the local elections so today we are recommending that, in addition to backing effective and hard working community advocates, people vote for candidates whose parties unequivocally back a people’s vote and will campaign to remain”.

That means the Liberal Democrats and Greens in England and – although she may not have been thinking about Northern Ireland – Sinn Fein and the SDLP, Labour’s sister party.

On the other hand, Leave supporters face a more difficult choice if they want to use these elections to protest against the government’s failure to deliver Brexit. Ukip has more or less ceased to exist on local councils and has in any case put off a lot of voters by embracing Tommy Robinson. Thus we might expect many voters to stay at home today, or to vote extremely reluctantly for Conservative councillors – many of whom will be advertising their disappointment with Theresa May over Brexit in an attempt to persuade their voters to turn out.

One important thing to look out for in the early hours of tomorrow morning, therefore, will be turnout. But the main question will be how badly the Conservatives do. The key indicator to look out for tomorrow will be the projected national vote share. The BBC and Sky News will produce (slightly different) estimates of how the whole of Great Britain (that is, excluding Northern Ireland) would have voted if the elections had been held everywhere.

In recent years, as can be seen from figures compiled by the former BBC head of political research, David Cowling, the two main parties have held the main shares, with variations – in particular a Labour slump during Gordon Brown’s time as prime minister. Ukip peaked in 2013, taking votes roughly equally from Labour and Conservative, but had all but disappeared by last year.

This time, the question will be how far the Conservative share of the vote falls, and which of their main rivals – Labour, Lib Dems and Greens – will benefit most.

For the prime minister, and for Brandon Lewis, the priority today is damage limitation. The European elections later this month are a write-off anyway: but the survival of the Tory party depends on rescuing as much of its activist base in local government as they can.

In Northern Ireland, where 11 councils are elected by a proportional system, the elections will be the annual test of the great struggle between unionist and nationalist blocs – and also of the balance of advantage within each bloc between the dominant and junior parties.

At the last elections in 2014 Sinn Fein won the largest share of the vote, 24 per cent, but the DUP, with 23 per cent of the vote, won considerably more seats (so the STV system in multi-member constituencies is not as proportional as all that). In 2014 the UUP – the inheritor of the traditional unionist franchise – won 16 per cent of the vote, giving the unionist parties together 39 per cent, while the SDLP won 13 per cent, giving the nationalist parties a total of 38 per cent.

Any shifts in those vote shares will have a significant if unpredictable effect on the attempts led by Karen Bradley, the secretary of state in London, to bring the parties together to try to re-establish devolved government in Belfast.

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