Alistair Darling, the Chancellor, who is defending a 7,000 majority in Edinburgh, and Ed Balls, the Schools Secretary, who is fighting a new seat with a notional majority of 8,500, are high on the hit list.
The Conservatives, who have a commanding 12-point lead in the opinion polls which is enough to propel them into Downing Street, are determined to take out some of Labour’s biggest beasts.
Mr Cameron and his inner-circle believe that tactical voting, which cost the Tories dear at the last three elections, will be deployed this time against some of the government’s most high profile supporters.
The Tories, buoyed by last month’s by-election victory in Norwich North and successes in the local council elections in May, want to inflict the same sort of dramatic defeat suffered by Michael Portillo when his 15,500 majority was destroyed in Tony Blair's first election landslide in 1997.
They will step up their efforts in Mr Darling’s constituency on the home turf of Jim Murphy, the Scottish Secretary, who has a 6,600 majority, Ben Bradshaw, the Culture Secretary, 7,500 majority in Exeter, the Blackburn constituency of Jack Straw, the Justice Secretary, 8,000 majority, and John Denham, the Communities Secretary, 9,000 in Southampton Itchen.
A senior shadow cabinet source refused to call it a decapitation strategy but said: “We are after some big scalps.Some of the more comfortable MPs, including Cabinet ministers, are starting to see more political activity. Those efforts will be stepped up.
“We not going to move ahead of ourselves but a number of senior ministers could go if the swing to us moves into double digits. Some Cabinet ministers should not feel safe. If we maintain a 12 point lead certain ministers, who would otherwise be taking a high profile role in Labour’s campaign, will be penned into their constituencies much more than they would prefer to be.”
The Tories are hoping that their tactics will lead to a repeat of the Lib Dems’ spectacular coup in the 1992 general election when they ousted Chris Patten in Bath when he was Conservative Party chairman even though Sir John Major went on to win the general election.
The shadow cabinet source said: “Certain Labour Party big beasts, and they know who they are, are already experiencing more activity on the ground from us. We are going to make Ed Balls and Alistair Darling and some of their ministerial colleagues feel very uncomfortable.
“They will not only be fighting their most difficult general election campaign on a national front in two decades but they will also have really tricky contests in their own constituencies.”
The Tories hope that by intensifying their efforts against some of the party’s most senior figures Labour’s scarce financial resources will have to be spread even more thinly to try to defend them. “We will hit them hard where they least expected it,” said the source.
But Mr Darling, standing in for Gordon Brown during his summer holiday, insisted yesterday Labour could still win the election despite a series of opinion polls showing a clear lead for Mr Cameron’s Tories.
The Chancellor, at a London Jobcentre, said: “I believe there is a choice. We are committed to helping people, especially at this time, but also to making sure that we have an optimistic view of the future, that we can make sure that we have jobs and opportunities not just for the present generation but for generations to come. I think when that choice is made people will see that there is a clear choice which is why I remain confident.”
Other Labour big hitters who face a concerted Tory push are Charles Clarke, the former Home Secretary, whose 3,000 majority in Norwich South looks shaky after Chloe Smith won the neighbouring seat in last month’s by-election to become the youngest Tory MP for 30 years. Jon Cruddas, a dark horse for the Labour leadership, is also in trouble in Dagenham where the BNP has made huge inroads into his vote.
It’s a potentially high risk strategy as the Lib Dems conceived a “decapitation“ campaign against the Tories at the last election which failed to remove any of their targets including Michael Howard the then party leader. The Lib Dems also have high hopes of capturing Birmingham Hodge Hill from the Cabinet Office minister Liam Byrne whose majority in Birmingham Hodge Hill was halved last time to 5,500.