What if none of them ends up in Number Ten?

Before the current election campaign got under way, there were some pundits who predicted that it could become the first such contest to be decided over the worldwide web.

But apart from one Labour candidate who made a fool of himself by using foul language on Twitter – the twit in question was swiftly forced to quit – talk of an ‘internet election’ has proved wide of the mark.

Instead, it has been the relatively old-fashioned medium of television which has led the way, with the debates between Gordon Brown, David Cameron and Nick Clegg proving to be the pivotal events in the campaign.

Indeed, they have assumed such a degree of significance that much of what has happened in between them has seemed a bit like waiting for the next course to arrive in a restaurant.

After the first debate, I wrote that it was beginning to look as though the will of the public in this election may be to deny both of the two main parties an outright majority.

At the time, it was a somewhat tentative conclusion, but the “Cleggmania” that erupted over subsequent days suggested it wasn’t far off the mark.

If proof was needed that it is the Lib Dem leader who is setting the agenda in this campaign, one need only look at how the second debate on Thursday contrasted with the first.

Whereas in the first one the prevailing attitude of the other two leaders was “I agree with Nick,” in the second one they were finding as much to disagree with him about as possible.

Another thing I wrote last Saturday was that the Lib Dems can expect an onslaught from the 'big two' over the next few days such as they have never seen.

In truth Labour has been rather muted in its criticisms, but the attacks on Mr Clegg in Thursday morning’s Tory-supporting newspapers will have done Mr Cameron’s party little good in my view.

The public has come to see that kind of journalism for what it is – not journalism, in fact, but merely an extension of the yah-boo politics they have come to loathe.

If the Cameron camp was hoping it would burst the Clegg bubble, it is already clear that it has signally failed to do so.

That said, both Mr Cameron and Mr Brown can certainly take heart from this week’s debate, which saw all three contenders much more evenly-matched than the previous one.

Indeed, Mr Brown’s ratings improved so markedly that he might even entertain hopes of coming out on top in the final, surely decisive confrontation this coming Thursday.

The Prime Minister is nothing if not resilient, and his “like me or not” passage in which he tackled his own lack of personal charisma head-on will have gained him a certain amount of respect.

There remains, though, a strong feeling in the electorate that, after 13 years and a record that can best be described as mixed, this government has finally run its course.

For that reason, we can expect to hear Mr Cameron continuing to hammer away at his core message over the next week that only a vote for him can spare us another five years of Mr Brown.

It is not, as it happens, strictly true. The price of a Lib-Lab pact could well be the Prime Minister’s head on a platter, in which case expect to see South Shields MP David Miliband summoned to the Palace.

Of all the possible denouements to this extraordinary campaign, that would surely be the most bizarre – that none of the three contenders who have slogged it out over the airwaves actually ends up in Number Ten.

The fact that such scenarios are even being discussed is a measure of just how unpredictable this whole election has become.

Tories win battle of ideas - but Clegg wins battle of personalities

Whether you take the view that politics is essentially about the big issues facing the country, or whether you see it as merely a clash of egos, there has been plenty to chew on this week as the election battle continued to shape up.

The 'policies v personalities' dichotomy was perhaps most elegantly summed-up by Denis Healey, writing about his former colleague Roy Jenkins in his autobiography 'The Time of My Life.'

"He saw politics very much like Trollope, as the interplay of personalities seeking preferment, rather than, like me, as a conflict of principles and programmes about social and economic change," he wrote.

So while Healey doubtless saw the publication of the parties' manifestos as the key event of the last seven days, Jenkins would have been more likely to incline towards Thursday's TV debate between the three main party leaders.

First off, then, the manifestos. In a nutshell, Labour's was the dullest, the Lib Dems' the longest and most detailed, and the Tories' by far the cleverest.

That is not to say the Tories had all the best ideas. Some of them - such as allowing local people to sack failing police chiefs and headteachers - may well cause more problems than they solve.

But the point is, at least are they are ideas, and at least they are fresh.

By going big on the 'new localism,' Tory leader David Cameron may well succeed in capturing the 'anti politics' mood that has gripped the country ever since the MPs expenses debacle of last summer.

The absence of such an overarching vision or ‘big idea’ in the Labour document, by contrast, seemed to underline the view that the party needs a spell in opposition to renew itself.

That impression was scarcely dispelled by the TV debates, in which a greying, seemingly exhausted Prime Minister was forced to square up to two younger, more vigorous and more charismatic rivals.

Mr Brown could have tried to use his greater experience to advantage, but perhaps constrained by the format, he seemed oddly reluctant to attack his opponents.

For instance, instead of trying to engage intellectually with Mr Cameron's claims that Labour’s National Insurance rise is about wasting money rather than cutting the deficit, he should have told him to stop talking rubbish.

The opinion polls have already declared Nick Clegg the big winner of the debate, and I have to say that confirmed my own impression

He made a slight fool of himself by refusing to say whether he agreed with Mr Brown's plans for a referendum on the voting system when we all know he would love nothing more, but that aside, it was an assured performance from the Lib Dem leader.

His best moment came when he pointed out that both parties had blocked his plans to allow constituents to recall their MPs in the event of serious wrongdoing.

This idea has since appeared in one form or another in all three parties' manifestos - a perfect illustration of how the old, adversarial politics frustrates real progress.

So will Mr Clegg's 'victory' change the dynamics of the contest?

Well, one thing is certain. The Lib Dems can expect an onslaught from the 'big two' over the next few days such as they have never seen.

But though it is still early days, it is beginning to look as though the will of the public in this election may be to deny both of the two main parties an outright majority.

If so, it is just possible that this could be the election that finally changes the face of British politics for ever.