The incumbency effect is hurting the Tories, not helping them

Local MPs aren’t helping the Tories overcome the great disadvantage our unreformed boundaries deal them.

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In a recent piece, the Times columnist Danny Finkelstein suggested that:

“Although everyone thinks the Tories need a lead to eliminate their disadvantage from constituency boundaries, this fails to take account of the advantage that new incumbents have in their first run for re-election. The best estimate is that these two effects cancel each other out.”

Conservatives shouldn’t be so reassured.

We have created something that allows you to translate the latest polling numbers into how many seats each party will win on election day. It shows quite how disadvantaged the Tories are under the boundaries.

In a system where no one party was disadvantaged, two parties would get roughly the same number of seats if they got the same number of votes.

But because of the way Britain’s constituencies work, Labour would win between 35 to 40 more seats if it tied with the Tories. In the graph below, figures have been held constant for the Lib Dems and UKIP at 8 per cent, and those for other parties adjusted to make 100 per cent.

Not changing the boundaries in this parliament was a catastrophic error for the Conservative Party. It has to win nearly 40 per cent of the vote to win a majority – but no party has done that since 2001.

The Tories haven’t won a majority for 22 years and it’s hard to see that changing now that Ukip commands 10-15 per cent of the vote.

Continue to to read the rest of this story.

Harry Lambert was the editor of May2015, the New Statesman's election website.