Theresa May's snap general election will be decided in 112 marginal constituencies -- seats with majorities of 10% or less that require a swing of 5% for the incumbent party to lose. The Prime Minister, who has a working majority of just 17 seats in the House of Commons, said she wants "unity" at Westminster as talks on Brexit begin in earnest with the European Union. May's commanding polling lead will see a fierce battleground across the Midlands, the North and in London suburbs as the Tories look to sweep up Labour seats. Professor John Curtice from Strathclyde University suggests the Prime Minister will need a lead of greater than 10 points to get the large government majority she wants to make her task of delivering a successful Brexit easier. The latest YouGov survey showing a Tory lead of 21 points suggests as many as 70 Labour seats falling to May - handing her a majority of around 140.
