The debate within Unionism is still raging about whether there should be a pact or not. The idea of a straight trade - one UCUNF, one DUP - seems to have been abandoned. Now the idea of unity candidates with no party political baggage that can be endorsed by both parties seems to be Plan B but the UUP continues its game of not saying No but not saying Yes either.
The tightening of the national polls means there is much number crunching going on with a hung parliament a possibility. John Rentoul of the Independent and James Forsyth of the Coffee House blog point out that Sinn Fein's policy of abstention reduces the number of seats a party needs to form a majority government. This means that for every Sinn Fein MP elected the Conservatives need one less Tory elected.
A split Unionist vote in Fermanagh and South Tyrone will ensure a Sinn Fein victory but because of the parliamentary maths, is a Sinn Fein MP as good as a Tory for Cameron?