Mary Ann Sieghart: A party that is growing up in public

The students have stomped out and slammed the door but there are millions of grown-ups who may decide to vote Lib Dem

When Nick Clegg looked oh-so-sincerely into the camera during the leaders' TV debates and promised that the Liberal Democrats would be different from the two main parties, millions of voters believed him. I groaned. When he said he was going to be more honest, I harrumphed. When he complained about the other parties' broken promises, I thought "Hmm... Hostage to fortune there."

I don't claim any great perspicacity. Most of the Westminster village thought the same. We all knew how dishonest the Lib Dems could be in their local campaigning. We had seen them saying one thing at one end of the country and another at the other. They were no more trustworthy than the other two parties, and as for broken promises – well, they had enjoyed the luxury of opposition for so long that they had never even had to try to put promises into action.

That is what enabled them to play student politics – literally – for so long. They thought they could afford to pledge to scrap tuition fees and spout specious slogans without having to think through the consequences of their actions. Now they have come up against the realities of government, and the realities have won. As Vince Cable said ruefully in the Commons this week, "I'd love to be Father Christmas and hand out lots of very popular policies and spend lots of money and not have to make difficult decisions." He had more than a taste of that in opposition.

Personally, I prefer the grown-up Lib Dems to their student predecessors. They are now a more serious party, attuned to the complexities of government, and no longer just a populist party of protest. They are genuinely trying to make the Coalition work and have earned the plaudits of their Tory ministerial colleagues. They have also succeeded in casting quite a liberal complexion over the Government and have an influence in the Coalition disproportionate to the number of seats – or even the number of votes – they won at the election.

But if the Lib Dems are at last starting to grow up, what about the voters? The extraordinary public anger that we've seen over the past few weeks – aimed almost entirely at Clegg not Cameron – looks just like dashed teenage idealism. The people who joined the "Cleggmania" during the election campaign had a hopelessly naïve view of politics. They believed the Lib Dems could deal with the deficit and scrap tuition fees just by taxing bankers. Well, wouldn't that be dandy? Trouble is, it was never going to be that simple, as both Clegg and Cable knew perfectly well.

Voters wanted more honest government and, in a funny way, that's what they've got. The Lib Dems are now, in effect, admitting that their manifesto pledge was unrealistic. Even if they had formed a majority Government, I can't believe that their priority would have been to abolish tuition fees. Yes, many of them have reneged on the NUS pledge that they foolishly signed before the election, but at least they are now being honest about the constraints of government and the tough choices involved.

Some people who voted Lib Dem at the last election will never forgive them. They prefer to shut their eyes, stick their fingers in their ears and chant, "La, la, la," rather than be told uncomfortable truths. At the next election, they will probably vote Labour or Green. These are people who never wanted the Lib Dems to form a coalition with the Conservatives anyway. They were bound to be disillusioned.

According to a poll commissioned by Lord Ashcroft, and published in the Sunday Telegraph yesterday, only 54 per cent of voters who supported the Lib Dems this year plan to do so again in 2015. Of course, five years is a very long time in politics, and many of these conceded that they might change their mind between now and then.

It will depend partly on how well or badly Labour is doing. In the Ashcroft poll, an astonishing 90 per cent of 2010 Lib Dem voters agreed that "Labour seriously lost its way on a number of important policy areas ... and will need to change a lot before people will be ready to vote for them again." And, in a ranking of politicians' performance, they put Clegg a respectable fourth, behind Cameron, Cable and William Hague, while Ed Miliband came 10th and last.

Interestingly, Ashcroft's pollsters also questioned 1,000 people who seriously considered voting Lib Dem in May but didn't do so. The results reflect the private polling that the Lib Dems themselves have done. The main reason why these "considerers" didn't in the end support Clegg's party was that they thought he would never be in government and it would be a wasted vote.

By May 2015, that fear will have vanished. Clegg, the Deputy Prime Minister, will be able to point to all that the Lib Dems have achieved in government, and where their liberal ideals have tempered the Tories' rawer instincts. Already, two-thirds of Ashcroft's "considerers" say the party has shown it is "prepared to take real responsibility, not just oppose from the sidelines", that it is "making an important contribution to the Government of Britain" and that "Nick Clegg is doing a good job as Liberal Democrat leader".

It's striking that twice as many "considerers" as Lib Dem voters say their opinion of the party has changed for the better since the election. And 25 per cent of them say they are now more likely to vote Lib Dem at future general elections than they were before.

This may not be enough to compensate entirely for the outflow of angry students and their supporters. But it's a start. The students may have stomped out and slammed the door on the student party, but there are millions of grown-ups out there who may decide at the next election that the Lib Dems have finally earned their vote.

There's another – possibly overlapping – pool of voters into which the Lib Dems may cast a fly. These are people who, perhaps to their surprise, have discovered that they really rather like Coalition Government. They like the way politicians from different parties have managed to find common ground and to govern together without sniping at each other. They like the way coalition has allowed both leaders to ignore the nuttier elements in their own parties. And they fear that a Tory majority government would be too red-blooded; the Lib Dems exert a welcome restraining influence.

Come the next election, they won't be able to vote specifically for another coalition – the ballot paper doesn't offer that option. But the best way to ensure a hung parliament will be to maximise the number of seats the Lib Dems win. This will be a powerful argument for Clegg to deploy in 2015: whether you want a coalition with Labour or the Tories, the easiest way to achieve it is to vote for us.

What he won't be able to do – and thank goodness for that – is a reprise of his 2010 election broadcast in which he was filmed walking through a snowstorm of discarded bits of paper. They were supposed to represent the main parties' broken promises. He knows he'll have to tidy up his own mess before he dares to complain again about theirs. With luck, that will make the next election campaign rather more honest than the last. And if we, the voters, have grown up too by then, we may decide to reward him for that.

m.sieghart@independent.co.uk

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