At the last General Election, the IFS calculated that the difference in public spending implied by Labour and Conservative economic plans was £40 billion. That’s about the size of the entire economy of Croatia.
Despite this it’s not unusual to hear the view expressed that there just aren’t that many differences between Labour and the Tories anymore. In an interesting article by Adam Ludlow, a pollster for ComRes, a Corbyn supporter is quoted saying:
“When I go out canvassing, people don’t say “you’re too left wing in the Labour Party”, they say “you’re all the same as each other!”’
The problem as Ludlow details is that more systematic evidence just doesn’t bear out such anecdotes:
…when it comes to the last election, the public was well-aware of the differences on offer – and chose to reject Labour.
The chart below shows that prior to the election, the vast majority of voters thought that Labour and the Conservatives were different in their visions for the future of the country, their attitude to the economy and their attitude towards government spending. Contrary to what some might say, the public did not think that the choice on offer was just different shades of austerity. Labour did not lose because they didn’t offer a big enough alternative to the Conservatives on the big issues.
If anything, this graph shows some of the reasons why the Tories won: the NHS was meant to be Labour’s core area of strength, but fewer voters thought the two parties were different in this area than in others.
Indeed, the key to marketing strategy is to be similar to your competitors on their areas of strength and different to them on your own areas of strength. Lower-end brands emphasise their similarities to their better-known counterparts in terms of quality while simultaneously highlighting their differences when it comes to price. Better-known brands try to turn this on its head, using the existence of replicas to draw attention to differences in quality (being “the real McCoy” or “Just like a Golf”).
The story of the 2015 election can, in part, be told by the way the Conservatives reduced the difference to Labour on the NHS while maximising the difference between the parties on the economy.
I suspect that the fact that Corbyn supporters so often return to this trope is an indicator that they are rather politically cossetted. It is quite possible if you live in the right (or should that be left) part of the country, do the right kind of job and have the right kind of friends to only really meet people who wish Labour was more left-wing. But people who live such lives should not mistake their social circle for the country as a whole.
Matter Of Facts 
‘Being the same as each other’ doesn’t have to mean your policies are all the same. It is entirely capable of being taken in a variety of ways.
It can mean ‘your presentations of your policies all feel the same, whether or not they are similar, because you use similar language and processes to produce them’.
It can mean ‘you all went to the same universities’.
It can mean ‘I am frustrated that I don’t understand what you are concerned about and why you don’t talk in language I respond to like I used to’.
It can mean ‘I no longer see how who I vote for results in who gets into power’.
It can mean ‘I felt tricked by Tony Blair’ (which isn’t the same as being ‘leftwing’, plenty of us who never voted Labour felt tricked by Tony Blair).
Well yes, I nearly wrote a paragraph saying as much. But the point is that many Corbyn supporters appear to think it does refer to policy and that it reflects a desire on the part of the electorate for someone with more left-wing policies. Which is to say the least a debatable assertion.