David Cameron could have the trickiest 2007 of all the main party leaders. At present, he appears to be in the strongest position: commanding media attention in a way that Mr Blair did before 1997. And the Tories have had their best year in the opinion polls since the early 1990s, at 37 per cent plus since May, compared with roughly 33 per cent for Labour, despite short-term fluctuations. (There is an excellent analysis of recent trends by Anthony Wells on the UK Polling Report website.)

After an initial advance late last year, however, the Tories have not improved their ratings as Labour has slipped. Populus polls for The Times have shown that the public likes Mr Cameron and believes that his party has a better team of leaders and is more united than in the past. Otherwise, voters’ views of the Tories, on caring about the problems of ordinary people, being honest etc, have hardly changed.

The Tory leadership hopes that the reports by various policy reviews and later party pledges will remove voters’ doubts about what it would do. But taking a firmer stand on the role and scale of the State, and hence of prospects for tax cuts, may fuel internal party criticism and provide ammunition to Labour.

Moreover, the party’s scope for action will be narrowed by the sharp slowdown in spending growth that will be confirmed in the March Budget.

The Tories face tough elections in May. There are hopes of gains in Wales, but Scotland is tough territory and comparison in England will be with the good 2003 results. At any parliamentary by-elections, Mr Cameron will need to do much better than the Tories’ close shave in Bromley last year.

The biggest challenge for Mr Cameron remains the arrival of Gordon Brown in No 10. While a Cameron-led Tory party is consistently well ahead of a Brown-led Labour Party in Populus polls, these are inevitably hypothetical questions, but the only pointers we have. The most interesting finding is that there is a lot of churning between parties, with one voter in five changing views. No one knows what will happen when the much-discussed handover happens.

The general view is that there will be a Brown honeymoon, and boost in the polls, for a time. Mr Brown is likely to have favourable coverage, at least on television, amid talk of a break with the Blair era, a fresh start, cleaning up government etc. He will be making the news from mid-summer well into the autumn. That will provide a big challenge for Mr Cameron about how to respond. It is quite possible that Labour will return to the lead in the polls: hence the talk about a general election in, say, spring 2008 (much more likely than this autumn).

Such a honeymoon may not, however, last long. While approving of his record as Chancellor, many voters do not really like Mr Brown and have doubts about him as prime minister. Labour’s problems are deeper than the replacement of Mr Blair by Mr Brown.

A large number of voters are dissatisfied with the Government and think that it is time for a change. So if Mr Cameron can weather a testing year, 2008 could be much better for him.

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