The latest tally suggests the Conservative wing of the government will lose this afternoon’s vote on the boundary review. They do not have the support of the DUP despite efforts in the last 72 hours to get it. Using Northern Ireland Secretary Theresa Villiers as the intermediary, the prime minister offered to exempt Northern Ireland from the boundary review.

The DUP is concerned that it will reduce its representation at Westminster. The bill being debated at this moment is also about lowering the number of seats in the Commons from 650 to 600 – Number 10 offered the DUP to reduce the number of seats to 602 instead. It was quite clear where the extra 2 would come from.

The DUP could see that this was only deliverable if the Tories could be sure their coalition partners would go along with it. The Lib Dems were adamant they would oppose such concessions but I understand that for the avoidance of doubt Nick Clegg made contact with the DUP himself yesterday to spell out in clear terms that his party would not support such an arrangement.

It must have been quite a conversation, along the lines of “I don’t know what that coalition partner of mine promised you but don’t necessarily believe him.”

David Cameron and Nick Clegg have opted to avoid the debate. They both want to keep emotions under control, particularly on the Tory backbenches. But Nick Clegg couldn’t risk an understanding between the Tories and the DUP blowing a hole in his strategy, which is to fight the Westminster seats on the same basis as the last election, he hopes advantaging his sitting MPs with incumbency and avoiding them having to get to know entirely new wards and streets in rejigged boundaries.

Labour strategists are  excited about what today’s vote means. This story may seem insignificant but all main parties think it goes to the heart of who can win the next election and who can’t. One Labour figure pointed out that elections tend to see swings under 5 per cent and the changes if passed could’ve been worth a critical 1.8% to the Tories.

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