Speaking at the launch of the Labour manifesto at Bradford University before campaigning in Huddersfield and Leeds, Mr Corbyn declined to put a figure on how much extra Government borrowing his plans would involve. People like me are always optimistic ... things can happen.
"I see leadership as not dictating but leadership is also about listening".
'I believe these next three weeks will throw up something that is quite extraordinary.
There was confusion over whether Labour's manifesto was committing the party to ending the freeze on benefits.
Many in the Labour Party will also view Mr MCluskey's gloomy forecast as a lowering of expectations so the Labour leader can cling to power after 8 June until a younger left-wing successor can be found.
His comments were dismissed by Labour's elections co-ordinator Andrew Gwynne, who said: "This is absolute rubbish from the Tories and yet another wholly cynical ploy to try and avoid scrutiny of their own spending plans". Some opinion polls suggest Theresa May and the Tories could win more than 400 on 8 June.
Both Gordon Brown and Ed Miliband resigned after leading Labour to defeats in 2010 and 2015 but, amid speculation that jockeying for position has already begun, there have been suggestions that Mr Corbyn could stay on if he equals the 30.4% vote share that Ed Miliband got in 2015.
The latest opinion polls have Labour around 30% or more with the Conservatives above 40%.
He suggested winning 200 seats - almost 30 fewer than in 2015 - would be a "successful" result for Mr Corbyn.
Politico quoted McCluskey as saying working class voters who plan to vote Conservative for the first time will do so "because their mind is being turned by the constant attack of the media on Jeremy Corbyn and the image that they've pinned on Jeremy".
On the chances of a Labour victory, Mr McCluskey said: In terms of the imagery of Jeremy, that's a huge task. You've got the guy.
"I am very proud that we have a party that is diverse, that is inclusive, that is pluralistic and this manifesto is a product of that process".
We're not going to repeat them here, but suffice to say the report is extremely slanted in a direction that we honestly struggle to recognise following years of following JME's work (and social media output). "Vote for Jeremy Corbyn. show us how it's done!"