Tony Blair stormed back into the political fray today, insisting: “Labour has every chance of succeeding”.

Joining the 2010 campaign trail for the first time to help salvage Labour’s re-election bid, Mr Blair denied Gordon Brown had been a failure as Prime Minister.

As Mr Brown campaigned in the West Midlands, his predecessor spent the day visiting marginal seats in and around London.

Asked whether Mr Brown had failed in his time at Number 10, the former PM said: “No, I don’t think he’s failed at all.”

On the prospect that the party could come third in votes next Thursday, he replied: “I don’t believe that will happen.I believe Labour has every chance of succeeding. But we will only

succeed if the focus is on policy.”
He said the TV debates had focused the campaign on the “ups and downs”, but he added: “When you get into the final days people will really focus their minds on who’s got the best ideas for the future.”

Mr Blair praised Mr Brown’s leadership of the economy, saying he had  the energy and drive to take the country forward.

Speaking during a visit to a health clinic in Harrow, a tanned and relaxed Mr Blair decided to have his blood pressure checked.

Asked if he thought it would be higher or lower than Mr Brown’s, Mr Blair replied: “It is a difficult job being PM  I know.”

It is believed Mr Blair was brought back to try and undo some of the damage caused by Mr Brown calling a pensioner he met in Rochdale “a bigoted woman”.

Mr Brown was forced to apologise in person to a lifelong Labour supporter, Gillian Duffy, after his unguarded remarks were caught on a microphone. She had complained about eastern Europeans “flocking” to Britain.

Mr Blair has not been publicly involved since he gave a speech in his old Sedgefield constituency earlier this month.

He used his first domestic political speech since he stepped down as prime minister in 2007, to rally support for Labour ahead of the start of the election campaign. Mr Blair set out why he wanted to see a fourth successive Labour victory and praised Mr Brown’s “experience, judgement and boldness” saying he had taken the right decisions to help Britain out of recession.

And he attacked the Tories saying their polices were “confused”.

Despite his huge private earnings and his role in the invasion of Iraq in 2003, Mr Blair has been dubbed “Labour’s secret weapon” and is thought to be able to appeal to Labour voters concerned about crime, immigration and tax.

It is thought he has also been earmarked to go to a range of seats in the north-west next week, including some that neighbour Rochdale, in Greater Manchester. Mr Blair led Labour to three successive general election victories and, although he and Mr Brown had an often difficult relationship while they were prime minister and chancellor, the two campaigned alongside each other to secure victories in 1997, 2001 and 2005.