Leadership contests often bring out the worst in parties. Candidates magnify differences and appeal to activists who are not typical of the party’s voters. That was true of the Labour deputy leadership contest and is the risk now as Nick Clegg and Chris Huhne battle to lead the Liberal Democrats.

Only when there is a clear front-runner, as with Tony Blair in 1994, David Cameron in 2005 and Gordon Brown this year, can the favourite afford to look outwards and present a fresh image to the public. This usually produces a honeymoon effect as the party’s ratings have risen sharply, both in anticipation of, and after, the change of leader.

Mr Clegg is the Westminster and metropolitan front-runner. There have been no polls so far, not because of a lack of interest but because of the practical problems of getting at 60,000-plus Lib Dem members. Even online polls in the Sir Menzies Campbell/Huhne contest of early 2006 were way off. So everyone is cautious. Mr Huhne starts from having done well last year, though neither he nor Mr Clegg is well known among less-active Lib Dem members, the armchair voters.

The choice is blurred by their similarities (both have foreign wives, were MEPs and went to public school and Oxbridge) and on policy. Attempts to claim big differences smack of pedantry and mean nothing to most voters. About the only exception is Trident, where Mr Clegg has stuck to the official, no need to commit yet, stance, while Mr Huhne has been more hostile (though, ironically, he is backed by some SDP founders who left Labour in 1981 partly over unilateralism).

Attempts to highlight the gap have often been ludicrous. For instance, the Huhne camp put out a silly press release yesterday calling on Mr Clegg to seek corrections from newspapers over what journalists had written.

The contrast lies more in style and positioning. A thoughtful analysis this week by Stephen Tall, on the Liberal Democrat Voice website, concludes that the essence of the contest is: “purism (Huhne) versus pragmatism (Clegg)”. Should a leader “unite the party around core beliefs”, or “unite the people around a broader concept of liberalism – one which the party perhaps sometimes finds uncomfortable – in the hope it will give the party mainstream appeal and, in time, power?”

A Populus poll for The Times, last weekend (see www.populus.co.uk) points to the potential for the Clegg view: 70 per cent agree that if the Lib Dems had “a strong and credible new leader, many more people would consider voting for them”, while 64 per cent believe that there is so little difference between the main parties that “there is a real opportunity for the Lib Dems . . . if they can develop some clear and distinctive policies”. There is no longer any pro-Labour bias among voters if there was a hung Parliament.

The Lib Dems have picked up a bit in the polls, but any new leader will have a hard task getting heard. The choice between Mr Clegg and Mr Huhne boils down to who can best reach out beyond the party faithful.

What people say:

70% of those questioned would favour the Liberal Democrats if they had a strong and credible new leader

64% think there is so little difference now between Labour and the Conservatives that there is a real opportunity to make a breakthrough if the Lib Dems can develop some clear and distinctive policies

54% say that if no party has an overall majority after the next general election, the Lib Dems should be willing to support whichever has the largest number of MPs

34% think the Lib Dems should work with Labour to keep the Conservatives out of government

Source: Populus for the Times, based on interviews on November 2 and 4

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