By Lord Ashcroft
Marginal constituencies decide the outcome of elections. In 2010, though the Conservatives did not achieve the national vote share they wanted, the party’s targeting strategy meant it won 23 more Labour seats and 9 more Liberal Democrat seats than it would have done on a uniform swing. Had it not been for the Conservative performance in the marginals, Labour would have been the largest parliament and would have continued in government.
The voters in marginal seats receive, no doubt to their delight, a great deal more attention from the parties than anyone else. But not all marginal seats are the same. Not only are they contested by different parties, they are home to different kinds of people and face a variety of different circumstances. Not only can the state of play in the marginals look rather different from the national polls, different kinds of marginal seat can look rather different from each other.
Now that we are past the midway point in the parliament – and now that it’s clear that the constituency boundaries will not be changing before the next election – I decided it was time for a proper look at the marginal territory where it will be decided who enters 10 Downing Street on 8 May 2015 and whether or not they have an overall majority at their command.