Despite spending much of the autumn of 2014 ruling out an election pact, the Democratic Unionist Party and the Ulster Unionists have this week gone ahead and agreed just that.
The DUP will not field candidates in Fermanagh & South Tyrone and Newry & Armagh, while the Ulster Unionists will not field candidates in Belfast East and Belfast North.
In each case, the party that is standing aside will encourage its supporters to vote for the other party’s candidate.
It’s an arrangement that is both pragmatic and political.
The most significant of the four seats is probably Belfast East. Naomi Long of the Alliance party won the constituency in 2010 by 1,533 votes. Both the DUP and the Unionists fielded candidates in that election, as they had done in every election since 1997. Long managed to beat both parties, in the process defeating DUP leader Peter Robinson.
This time the Ulster Unionists are standing aside in the hope that its supporters will swing behind the DUP candidate Gavin Robinson and in the process defeat Long.
You’d have to say this now seems a distinct possibility, though some voters may take umbrage at being denied a proper choice. A DUP gain in Belfast East would not just wipe out the Alliance party’s representation in the Commons. It would also boost the DUP’s numbers in the Commons by one, in turn giving the party more sway in a hung parliament.
The other seat in which the Ulster Unionists are standing aside is Belfast North: already a DUP seat, but one that Sinn Fein’s Gerry Kelly is hoping to take, having come only 2,224 votes behind Nigel Dodds in 2010. This year will be the fifth time Kelly has tried to take the seat for Sinn Fein. But if Ulster Unionist supporters swing behind Dodds, the DUP ought to retain the seat easily.
The two seats in which the DUP is standing aside probably won’t see any change. Both are currently held by Sinn Fein: Newry & Armagh, where Conor Murphy won a majority of 8,331 in 2010, and Fermanagh & South Tyrone, where Michelle Gildernew won by just four votes: the smallest majority in the whole of the UK.
Gildernew has experience of standing against a so-called “unity” candidate. In 2010 the DUP and Ulster Unionists both stood aside in her constituency and urged their supporters to back the independent candidate Rodney Connor. Gildernew still won, albeit by a tissue-thin margin.
My instinct is she will cling on again this year, but the result could be close. She has been the MP for the seat since 2001. Sinn Fein holds three of the assembly seats for the constituency, while the DUP has two and the Ulster Unionists one.
If the UU do win, however, it will mean the party will be back in the Commons for the first time since 2010. And it will almost certainly side with the Conservatives in any coalition or minority administration.
The DUP-UU pact is one that may only affect a tiny handful of seats, but it could have big consequences for the stability and composition of the next government.