What to make of that quartet? There is much that is sensible, much that is not, and still more that is unworkable. An economy that is driven by enterprise in emergent technology, a very exportable commodity, is self-evidently sensible and has the support of both Cameron and Mandelson.
Nick Clegg possesses the most attractive policy in British politics. Raising the income tax threshold to £10,000 is a fair and hugely popular measure that is, unfortunately, a peacetime luxury. The Liberals want to fund this cut through an ill-thought out 'Mansion tax'. Aside from the political problems both Labour and the Conservatives would have with super taxes, the mansion tax will not plug the gap left by removing 4 million taxpayers' liabilities. Exactly the same applies to the 'pupil premium' in the short term, though I doubt Labour or the Tories would object to a short-term boost in principle. Electoral reform is a pipe-dream, but will be a condition of any and all co-operation. The minority government's survival would rest on delivering electoral reform in the medium to long term of a hypothetical alliance.
There is consensus. Co-operation and perhaps even a coalition could be built in the event of a hung parliament. Whether that would prove durable is another matter.