Cameron joins Sir Ian Botham on second leg of charity walk

The Tory leader took his campaign battlebus to Sutton Coldfield in the West Midlands where the cricket hero – nicknamed "Beefy" – was completing the second leg of a series of 10 treks through 10 towns.

Mr Cameron joining up with the former England captain in Sutton Park for the last four miles of the walk from Birmingham town centre before meeting other participants and supporters yesterday.

It came as a series of opinion polls suggested that despite comprehensively winning the opening skirmishes with a promise-strewn week of visits right across the UK, the party is still short of the support it needs for an outright win on May 6.

There was a surge of Liberal Democrat support in the must-win marginal seats – some of which have been targeted on the regional tour.

Yesterday's visit was in the safe seat held by Shadow International Development secretary Andrew Mitchell with a 12,000-plus majority.

Before setting off from his London home, Mr Cameron showed off the bus – one of three being used for the tour along with trains, planes and cars – to pregnant wife Samantha and their children Nancy, six, and Elwen, four.

Sir Ian has embarked on the latest tour as he marks the 25th anniversary of his John O'Groats to Land's End walk.

He is walking through 10 towns in 10 days for charity Leukaemia and Lymphoma Research.

Starting in Manchester on Saturday he will go on to Worcester, Bristol, Winchester, Epsom, Reading, Milton Keynes and Chelmsford before finishing his trek in London on April 19.