John Rentoul: Take a peek into my crystal ball for 2011

Predictions are a dangerous business. Serious risk of opening oneself up to ridicule,and possibly even contempt. So, let's do it

I predict that next year will be a prime number. Anything beyond that is risky. I do not want to be in the same position as Craig and Jane, who predicted that this year "quantum physicists discover extraordinary way to generate electricity from water". Although there are still four days to go. Craig ("£1.50 per minute – pay by credit card or add to your phone bill") claims credit for some of his other predictions: "France did make some threats about leaving the euro. Many clergy became Catholics – a trend that is still continuing now. Holiday firms, building companies and aviation companies went bust. However, Victoria Beckham did not get pregnant as predicted, and I was wrong about Gordon Brown being forced out of office before the election." Mind you, he was not alone there.

As I say, a dangerous business. Serious risk of opening oneself to ridicule and possibly even contempt. So, let's do it.

Oldham East and Saddleworth. By-election on 13 January. Labour gain.

Welsh referendum, 3 March. Labour-Plaid Cymru gain.

Alternative Vote referendum, 5 May. Lib Dem loss.

The economy. Petrol prices, VAT, National Insurance and public spending cuts. Conservative gain.

That just about wraps up the political year. There are also several ball-based public entertainments. The cricket seems to be going well. Later will be the other kind of cricket that they play quickly (it's a relative term) in their pyjamas. Before that, I have high hopes that the Philadelphia Eagles will make it to the Super Bowl on 6 February. Later in the year, the rugby World Cup is in New Zealand.

But perhaps I had better explain my politics predictions. The first scheduled test of the year will be the "Old and Sad" by-election. Describing it as a Labour gain is not strictly accurate, as the prediction is that Labour will hold the seat vacated by Phil Woolas, whose election by 0.3 per cent of the votes has been declared void by the electoral court. However, in the circumstances, for Labour to keep the seat would be a morale-booster for Ed Miliband. Those circumstances being the London view that Woolas was disgraced, that Miliband's leadership is in trouble and that the Liberal Democrats think they can win it.

None of those is really true. I was in Littleborough and Saddleworth, as much of the constituency then was, when the Lib Dems won the 1995 by-election. I was in the pub that was their campaign HQ as they were singing "Walking in a Liberal Wonderland" into the small hours. Woolas lost, but he won the redrawn seat in the general election and he was popular there.

So I doubt that many local voters care that much about his rough tactics in the last election. Those who do care would probably never vote Labour anyway and, in any case, Labour's new candidate, Debbie Abrahams, is, as far as anyone knows, innocent by dissociation.

Unless there is a big surge of local anti-Labour sentiment, therefore, Abrahams is likely to win. In national opinion polls, Labour is 10 percentage points up on its general election vote, and the Lib Dems are 13 points down. Having been neck-and-neck in the constituency, that means that Elwyn Watkins, the Lib Dem who brought the court case against Woolas, starts from a long way back – and his party's change of policy on tuition fees hardly helps him.

That is why, incidentally, there is discontent among Conservatives that the Prime Minister wished the Lib Dems well in the contest, and has let it be known that he wants to soft-pedal the Tory campaign to assist Watkins. The Tory vote nationally has held firm since the general election, which means that a simple extrapolation suggests that they should be Labour's main challenger in the by-election. This view is attractive to the bone-headed tendency on the Tory backbenches, and overlooks the dynamics of tactical voting: Tories might vote Lib Dem in the constituency, but Lib Dems are unlikely to vote Tory. In any case, Cameron is merely being polite. He knows it is a lost cause, but at least he can tell Nick Clegg he tried.

So, a good day for Ed Miliband on 13 January. And another bad day for Nick Clegg on 5 May, when the referendum will be held on changing the voting system. The Labour Party – which had been bounced by Gordon Brown into supporting electoral reform in its manifesto – has decided that it does not like coalitions (can't think why), so now anything that smacks of proportional representation, even if it isn't, is seen as an evil Cleggy plot.

The Alternative Vote – which simply means numbering candidates in order of preference – might be a bit more proportional in Britain; but only if the third party continues to attract a lot of votes, which may be a bit doubtful after five years of coalition. And if Labour is not campaigning enthusiastically for a Yes vote, it is hard to see how the forces of small c conservatism and misrepresentation can be beaten back. Especially when so many Lib Dems and electoral reformers themselves are so lukewarm about AV, which they regard as a "miserable" (Clegg's word) pigeon-step towards the fully proportional systems they really want.

Which is a shame, because AV would be a small step towards giving voters a little more power – hardly any need for tactical voting and fewer wasted votes. But that is by way of an aside, because the political consequences are likely to include the further erosion of Clegg's credibility and the Lib Dems' standing.

Nor is there much prospect of a respite for the Lib Dems in the other festivals of democracy in the next year. The referendum in Wales is likely to approve greater law-making powers for the Assembly there, which will be seen as an advance for the Labour-Plaid coalition. There is not much reliable polling on the Welsh, Scottish and Northern Irish elections in May, but we do not expect much change and certainly no advance for the Lib Dems in Edinburgh or Cardiff.

If we put Clegg to one side, then, as the voters seem inclined to do, what will influence the contest between Cameron and Miliband over the next year? The assumption among left-wing clairvoyants is that, once next week's VAT rise, the National Insurance rise in April and the spending cuts start to bite, the voters will flock to Labour's standard. Just as they did in the last two periods of fiscal retrenchment, in 1979-81 and 1990-92. Oh.

Only this week, Labour folk were congratulating Andy Burnham, now education spokesman, on forcing a second policy reverse on Michael Gove; this time on a free book scheme of which I had never heard; last time it was over school sports, which everyone agrees is a Good Thing but no one actually cares about. These are chimera. The compilers of "Cameron's U-Turns" do not realise that they are enumerating his strengths. A liberal conservative Prime Minister who is flexible enough to adjust his policy details while taking credit for the big, hard decisions needed to balance the nation's books.

I predict a bad year for Nick Clegg; a bad year that will feel like a good one for Ed Miliband; and only one winner.

John Rentoul is chief political commentator for The Independent on Sunday

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