Daniel Hannan is an MEP for South-East England, and a journalist, author and broadcaster. His most recent book is How we invented Freedom and why it matters.

First-past-the-post is groaning and swaying under the strain. Our voting system was designed for two blocs: a government and an opposition. You can see it in the layout of the Commons chamber. But over the past five years we have moved from a two-and-a-quarter party system to a five or six party system. The old argument for first-past-the-post – that it boosts the larger party and so provides stable government – no longer applies. These days, it throws up anomalous, unpredictable results that are only distantly related to how many people supported each party.

A number of factors have contributed to the change. A decade ago, Douglas Carswell and I co-authored a book called The Plan which, among other things, predicted that, as traditional loyalties broke down, people would increasingly shop around for niche parties. The Internet has played a part, as has the introduction of proportional representation at various non-Westminster elections: voting is habit-forming and people who have backed smaller parties at, say, Scottish or European elections cannot automatically be recalled to their older national allegiances.

First-past-the-post worked in the eighteenth and nineteenth centuries, when MPs were independent and parties were loose alliances. It’s hard to imagine that anyone would invent it today. For many Conservatives, of course, this is no argument: lots of things that we wouldn’t invent today work perfectly well. As Edmund Burke kept telling anyone who’d listen, it’s not enough to find a theoretically better alternative – you have to find an alternative that is better by a sufficient margin to justify the inevitable disruption involved in adopting it. But I think we have reached that point; and I think that growing numbers in all parties can see it. The only clear beneficiary of first-past-the-post today is the SNP, which aims to dictate policy to the next government with less than four per cent of the national vote.

Before sketching out what my preferred alternative is, let me deal with three likely objections – two from Conservatives, and one from non-Conservatives. The two Tory objections are “Leave well alone” and “Why are you raising this subject when we should be straining every sinew in the election campaign?” The converse objection is “Too late, you Tory numpty, you had your chance with the AV referendum”.

To take them in turn, the Conservative objection to electoral reform is about more than Burkeian scepticism. During the 1980s, many Tories reached the view that only first-past-the-post made Thatcherism possible. The permanent coalitions implied by proportional voting would, they believed, condemn Britain to sclerosis. This may have been true, but not because of any property intrinsic in first-past-the-post. It just happened that the Right at that time benefited from the Labour-SDP split as the Left now benefits from the Conservative-UKIP split.

Human nature being what it is, most politicians are either consciously or subliminally influenced by what suits their party when they pronounce on the ideal voting system. But party advantages shift like sand dunes in desert storms. It’s wiser to work out what is right in principle: no one can tell which system will favour which party in a decade’s time.

To say that we have always had the current system is, in any case, untrue. We have had multi-member constituencies in the past, and have repeatedly altered our voting system since 1832. If change is coming, we should take ownership of that process, as Disraeli did in 1867 – arguably the finest manoeuvre of the old shyster’s career.

To those who say, “Why raise this now when you should be campaigning?” I’d say two things. First, I am campaigning. Please join me: I’m in Brighton Pavilion and Hove today, Crawley and Horsham tomorrow, then Portsmouth, Southampton and Eastleigh. More to the point, though, this is precisely the kind of question that ought not to rushed as part of a coalition deal. Last time, we ended up with a referendum on a system that almost nobody had wanted. Why? Because four exhausted men needed to agree something quickly.

So let me say this now, before we know the election result. Instead of scrabbling to cobble something together after polling day, we should agree that a Royal Commission will put the options before Parliament in time for a referendum in, say, 2018. Any new electoral method would come into effect only five years after that – in other words, three elections from now. This would reduce the incentive for parties to try to game what was to their advantage, and instead focus the debate on the merits of the competing systems.

Which brings me to the non-Tory objection. The reason I opposed AV in the referendum – after some agonising – was that it was so obviously intended to favour a particular outcome, namely the election of more Liberal Democrat MPs. Though I was in principle in favour of electoral reform, I couldn’t support something so squalidly self-serving. At every public meeting, “Yes” campaigners would begin by apologising for the fact that they were proposing a system they had previously been rude about. And, sure enough, voters saw AV for what it was: a politicians’ trick.

The system that most electoral reformers had actually supported, when it was a question of principle rather than of Lib Dem advantage, was the Single Transferrable Vote (STV), and you can see why. STV retains a constituency link while ending the concept of a safe seat, because it allows MPs to be ousted by more popular candidates from their own parties. Voters like it and, while it isn’t proportional in theory, it tends to be in practice. It encourages candidates to campaign as individuals, as local champions, rather than as representatives of their parties. It thus has the incidental effect of strengthening backbenchers against Whips, and the legislature against the executive.

Every system has its pros and cons, obviously, but you can learn a lot from the way in which opponents attack something. In Ireland, STV is popular with almost everyone except (in private) politicians. Why don’t Ireland’s TDs and MEPs like it? Because, as a Fine Gael friend put it to me, “Instead of acting in the national interest, I have to do what my constituents want.” That’s the whole bloody idea, I told him: it’s called democracy.

I know what I’m saying won’t be popular with ConservativeHome readers. Many of my fellow Tories are comfortably settled into trenches, and won’t easily be drawn into no-man’s land. But the fragmentation of the old party system makes some form of change inevitable, sooner or later. The question is whether we want to be involved in that process or whether – as with Scottish devolution or Lords reform – we end up leaving it to the Left to design the new system. Think about it. In the mean time, if you’d like to help with some canvassing, we’re meeting at 11.30 this morning at 23 Old Steine, Brighton.