Nicholas Whyte: what will general election bring after this year’s seismic shocks?

Cartoon for 2017 general election supplement. By Brian John Spencer
Cartoon for 2017 general election supplement. By Brian John Spencer

Here we are again.

This year, 2017, has already been a seismic one in Northern Irish politics.

The Assembly election in March saw unionists lose their majority at Stormont, slipping to only one seat ahead of nationalists (though rather further ahead in terms of vote share).

Unionists now have only one MLA out of the five representing each of South Belfast, South Down, Newry and Armagh, Mid Ulster and West Tyrone – all seats that actually elected unionist MPs to Westminster in the not very distant past.

If a similar shift were to play out for the June 2017 Westminster election, what would the effects be?

There are six constituencies where the party that got the most votes in the March 2017 Assembly election does not currently hold the Westminster seat.

With pleasing symmetry, in three of those cases the DUP got the most votes and in the other three it was Sinn Féin who emerged on top.

The seats under threat are the three held by the SDLP, the two held by the Ulster Unionist Party, and the Independent MP for North Down, Lady Hermon.

Past voting behavior is often the best guide to future votes, though it is not infallible.

Let’s look at those six seats – and a couple of others, where the incumbent may be in difficulties despite their party’s success in March.

Sinn Féin are now seriously challenging the SDLP in two of the latter’s three remaining seats, South Down and Foyle.

In both cases, the SDLP majority over Sinn Féin in 2015 was around 6,000 votes.

In Foyle, Sinn Féin gained 5,000 votes between last year’s Assembly election and this year’s; in South Down, they gained over 6,000. (In Foyle, the SDLP also gained a couple of thousand votes; in South Down their vote remained static.)

Even allowing for the tendency for voters who may support unionists or Alliance at other elections to give the SDLP a helping hand for Westminster, this is enough to put both seats in play, with South Down looking the more vulnerable of the two.

Both of the seats won (against my expectations, I have to admit) by the Ulster Unionist Party in 2015 are under threat, from different directions.

In Fermanagh and South Tyrone, Tom Elliott is defending a 530-vote majority against SF’s Michelle Gildernew.

Sinn Féin’s vote here increased by more than 3,000 between the two recent Assembly elections, and they won three seats out of five this year rather than two out of six last year.

The combined unionist vote in this year’s Assembly election was just ahead of the total for SF; but one can expect SF to squeeze the SDLP vote for all it is worth. This is a very tough defence for the UUP.

South Antrim, where Danny Kinahan displaced the DUP’s veteran William McCrea in 2015, is a different matter. Both unionist parties gained roughly a thousand votes each between the two Assembly elections. In the context of a higher turnout, this actually meant a lower vote share for both.

Those new voters who did not vote for either of the main unionist parties earlier this year may be more inclined to support the incumbent; but with a new DUP candidate, Paul Girvan, will they be as strongly motivated? I find this very difficult to call.

North Down is only on my list because Lady Sylvia Hermon did not contest the Assembly election. Not counting her, it’s clear that the DUP are the strongest party by far in the constituency. But she counts for a lot.

Peter Weir got 35% of the vote to Lady Hermon’s 50% in 2005, when she first defended it for the UUP; when she first defended it as an Independent in 2015, Alex Easton (who is again the DUP candidate this year) got less than 24%, to her 49%. It’s a tough mountain for the DUP to climb.

South Belfast is by far the most unpredictable constituency in this election.

Alasdair McDonnell, then the leader of the SDLP, held it in 2015 with the lowest vote share ever recorded for a winning candidate in a single-seat Westminster election. The Assembly election saw the DUP 600 votes ahead of the SDLP, with Alliance and Sinn Féin less than a thousand behind.

It is remarkable for a party with only one MLA out of five to win a Westminster seat in a competitive election, but that is certain to happen here (unless the UUP or Conservatives pull off an even more surprising result). My inclination is that this is the most likely seat for a DUP gain, ahead of South Antrim, provided that they are able to squeeze the other unionist candidates. But McDonnell has tended to run ahead of his party.

Two other seats in Belfast also may well provide anxious moments for the DUP.

In East Belfast, Naomi Long, now Alliance Party leader, is fighting to regain the seat that she lost by 2,600 votes to Gavin Robinson of the DUP in 2015. There was no other Unionist candidate then; the UUP alone got 4,000 votes in the 2016 Assembly election, and 5,000 in 2017, so their challenge this time must put the DUP under pressure. Having said that, some UUP votes this time will also come from Alliance, who will need a pretty clean sweep of all the non-unionist votes to repeat their success of 2010.

Finally, some optimists on the nationalist side are looking with hope at North Belfast, where a fresh Sinn Féin candidate may unlock support that had not previously come to the party.

Perhaps. In the March 2017 Assembly election, the total vote for unionist parties, though at a historic low, was still a hair’s breadth ahead of the vote for the SDLP and SF combined, and more than 5,500 ahead of SF alone.

It seems unlikely that the other constituencies will provide many surprises. The DUP should hold North Antrim, East Antrim, East Londonderry, Lagan Valley, Upper Bann and Strangford comfortably; and Sinn Féin should also hold West Belfast, Mid Ulster, West Tyrone, and Newry and Armagh.

That is, unless something unexpected happens. But as a wise man once said, it is always very difficult to make predictions; particularly about the future.

• Nicholas Whyte is a visiting professor in the faculty of social science, Ulster University, and a senior director in the Brussels office of APCO Worldwide