If the referendum is to spark wider change, we need an alternative for the rest of the UK as powerful as Scottish independence.

What is driving the contagious passion behind the growing support for a Yes vote in the Scottish referendum? The ICM telephone poll published last week is clear. The three over-riding motivations are:

What is driving the contagious passion behind the growing support for a Yes vote in the Scottish referendum? The ICM telephone poll published last week is clear. The three over-riding motivations are:

• "feelings about Westminster and the type of politicians there" (51% of Yes Voters)

• "your feelings about Scotland" (41%)

• "your hopes of a more prosperous future for you and your family" (41%)

Concerns about the future of public services (24%), dislike of the City of London (18%), and remarkably, feelings about the UK as a whole (6%) trail very far behind.

So, as one might expect, Scottish identity is driving the Yes vote but equally, or even more important, it is a dislike of Westminster politics and the hope that an independent Scotland will lead to greater personal prosperity.

Should the vote go Yes on Thursday or should it just be close, these findings must stand as the loudest wake-up call to Westminster in decades. The Union will have been lost (or come close to being lost) not because of the "lies" of the Yes campaign or the ignorance of the risks of going independent but because half the Scottish electorate have lost faith in the way decisions are taken at the heart of government and believe they would be materially better off without Westminster politicians leading them.

It is now clear that the referendum has provided a focus for anti-Westminster feeling that has almost certainly been simmering away in Scotland for many years. Most importantly, it also offers a very clear alternative to Westminster.

The urgent question Westminster politicians should be asking themselves is what might provide a similar focus and alternative in the rest of the UK. I say this not because I think most of our politicians really care about serious constitutional change but because if they don't find the answer to this question they risk being caught off-guard and drowning in the deluge.

That deluge is already lapping at their heels in the form of UKIP. Luckily for our mainstream parties, Farage & Co. are handicapped by their hard right positioning on economic, EU and social issues. This means they will always find it difficult to become a major focus for anti-Westminster feeling that draws in support from across the political spectrum in the way the Yes campaign has (which, with the exception of Conservative supporters, the ICM poll also shows). In reality, UKIP muddy the anti-Westminster waters.

In a fit of absent-mindedness, mainstream politicians might follow Iceland's example (HT Rick Muir) and seize the moment by establishing a constitutional convention to direct and resolve the crisis of trust. In fact, the Electoral Reform Society and others have called for just such a move. But it is very hard to believe that a political establishment that still hasn't completed reform of the House of Lords after a century of debate and cannot even bring in a relatively minor change such as recall of MPs could take such a bold step. The very strong vested interests in Westminster mean that the political class would either never manage to establish a constitutional convention or would do so in such a way that any convention's recommendations could be safely watered-down to homeopathic ratios destroying its credibility from day one.

A Popular Movement for Change

The truth is if change is going to come, it has to come from the population itself; just as the pressure for Scottish devolution and then a referendum built over years to the point where it could no longer be resisted. What might galvanise such a popular movement?

The classic constitutional reform agenda of a written constitution, PR, Bill of Rights etc has shown itself unable to mobilise widespread support. Its driving ideas are shaped by a 19th century conception of what makes for a 'good' liberal democracy rather than 21st century demands for popular voice and control.

Devolution in the form of regional assemblies may have purchase in Wales and (more controversially) in Northern Ireland but as the 2004 effort showed they do not excite widespread support in England. People feel that such assemblies will simply mean a multitude of petty Westminsters across the country.

The only idea which could meet those contemporary demands for voice and control and bring about a meaningful shift in the conduct of Westminster politics is a radical reformulation of the role of our elected representatives.

If we were to have a referendum in the rest of the UK that could catalyse anti-Westminster sentiment into something positive and hopeful, it might just be about whether MPs' and councillors' prime legal responsibility should be to discover, aggregate and represent the settled views of their constituents on major pieces of legislation in Parliament. Only that might persuade the voters that MPs and Councillors really will finally be dragged away from the centripetal force that is the party whips and London media and put their constituents first.

Be under no illusion, however, that even if the Scottish epicentre unleashes an earthquake across the Union, it will take long years of vigorous campaigning to bring about such a change. Westminster may not be very good any more at securing popular support but its capacity to resist real change remains as strong as ever. And that, in a sentence, is the source of the current crisis.

These themes amongst others will be explored in my new book, Small is Powerful: Why the era of big government, big business and big culture is over (and why it's a good thing). You can pre-order the book and help its publication here.

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