To be fair to Labour.. they get blamed for the financial crisis, where actually we didn't perform that bad compared to other nations at the time..
And to be fair to the tories.. they get blamed for slow growth and recovery, where actually we didn't perform that bad compare to other nations at the time..
The issue for Labour is that the global economy is slowing, and there isn't the huge global rush that they can ride as they did in the early 2000s under blair. Unless they get lucky and we hit another revolution in industry/productivity as happened with the internet revolution in the early 2000s, the only two ways they are going to fund their plans are: Tax more, or Borrow more. As long as they are honest about this, I have no problem with them planning on spending, but they need to be honest.. yes you can tax the rich a bit more. But they are the most mobile citizens we have. Many will leave, many businesses will leave, and in the end it will be the middle class who pays. That might be fine - put to the people and say the truth: You will pay more, but you will get X/Y. Just don't lie and say "you won't pay more, only those pesky millionares will.. and you will get more".
As for the torries, they need to be honest and just say "Look, we can't ballance the books because the people of the UK are not actually willing to pay the price of living within their means, and its becoming increasingly un-electable for us to try... so we give up! Lets just spend now, **** our previous convictions, and hope to win a few elections while we can before our kids realise what weve done".