But, in a move seen as an attempt to appeal to the right, he has pledged to pull his party out of the European People's Party in Brussels.

BBC: David Cameron

In another leader you appeal for the English football team to pull out of the World Cup if their fans commit any more mayhem.

ECONOMIST: Justice in the world

Paperwatch: Jackie Ashley writing in The Guardian likens possible contender Kenneth Clarke to the late Mo Mowlam in terms of his popular appeal and warns Labour that he could well be the one to pull in the votes of "floating voters, disaffected ex-Tories and disillusioned ex-Labour voters".

BBC: David Cameron

You have other ecosystems looking to be purchased, and while they can appeal to the undecided in the middle, they have a much stronger pull on those who are transitioning from feature phones to smartphones, although family loyalties can influence the first purchased smartphone, the rise of the smartphone means that each week there are far more new customers than there are new voters.

FORBES: Ever Noticed That The Smartphone World Is Just Like A Presidential Debate?

In short, Mr Bradley may pull the Democrats towards a fight over who has the greater appeal to the left-leaning parts of the party.

ECONOMIST: The Democratic campaign