JEREMY CORBYN could provide the political “antidote” to Labour’s “Blairite virus,” according to the leader of one union which announced its backing for his leadership campaign yesterday.

After winning the endorsement of Unison on Wednesday, Mr Corbyn was further boosted by nominations from postal workers’ union CWU and rail union TSSA.

It means the bookies’ favourite and poll frontrunner now commands the support of six affiliated unions — double that of closest rival Andy Burnham.

Announcing the CWU decision, general secretary Dave Ward said: “We think that it is time for a change for Labour.

“The grip of the Blairites and individuals like Peter Mandelson must now be loosened once and for all.

“There is a virus within the Labour Party and Jeremy Corbyn is the antidote."

TSSA made its decision after all the leadership and deputy leadership candidates had been interviewed by the union’s national executive yesterday morning.

General secretary Manuel Cortes said he was “delighted” at the executive’s verdict, adding: “People are fed up of machine politicians who never give an answer.

“Jeremy is straight-talking and puts forward sensible policies which resonate with ordinary people.

“Jeremy is clearly articulating why we must end the austerity quagmire and that Labour’s economic policies must move on from failed neoliberalism.”

The unions cited Mr Corbyn’s long-standing support for renationalisation of the railways and Royal Mail respectively to explain why they had given him their support.

Mr Corbyn branded the privatisation of the two industries a “bad idea based on short-term profits, not long-term public good” as he welcomed the union’s endorsements.

He hailed them as proof that “people from all walks of life are coming together to support high-quality services, a public investment strategy to bring secure jobs, affordable housing and a Britain based on creating shared prosperity, not continual austerity for the many.”

Nomination from both unions also boosted Angela Eagle’s chances in the deputy leadership contest.

Meanwhile, Mr Corbyn won another seven nominations from constituency Labour parties on Wednesday night, taking his total to 133.

Over 500 people have signed up to hear him speak tonight at a rally in Leicester, the home city of Blairite rival Liz Kendall.