In his recently-published biography of Margaret Thatcher, he discusses her three successive election victories, the machinations that saw her leave Number 10 and her subsequent influence on the party she once led.

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With the candidates from each and every party saying that a vote for them will give us a better life/ country/ tax system etc., what is the point in trying to believe anything they say? I believe the only candidate one can have any trust in is the one who consistently tells the truth, good or bad, without manipulating it in any way. What do you think? If politicians were more honest, would people be more likely to vote? Lee John, Southport

Politics is like advertising: there is a good deal of deliberate deception, but little outright lying. There is certainly no reason to give up on the whole business. Be sceptical, of course, and try to read the small print, but don't assume that politicians will always behave badly. Many of their causes are honourable. Politicians should not always blurt out the truth; it may be far more damaging than remaining silent. In Northern Ireland, British politicians should refuse to answer the question: who won the war - the IRA or the government? When conflicts need to be resolved we need politicians. It is a mistake to despise their skills, which may involve obfuscation, changing the subject and not being frank. The mistake is to see them as spiritual leaders, or fountains of moral authority. They are often no more than "fixers". But that can be valuable, and sometimes even inspiring. It also often becomes our history.

In your opinion, has anyone landed a telling blow in the campaign so far? Jo Goodwin, Sale

Whoever asked the question of Charles Kennedy that forced him into an embarrassing mumble over his party's taxation plans is an obvious candidate for a campaign medal. Many Liberal Democrats would love to fight the election campaign as a radical alternative to Labour, serious about income redistribution and, in general, left-wing. But their problem is that the Liberal Democrats' main hope of a breakthrough in terms of parliamentary seats is by appealing to disillusioned Conservative voters, so they need to be rather right wing. It is enough to make any sensible chap, including Charles Kennedy, mumble when the key issues are raised.

If the Tories lose, will Michael Howard resign - and if so, who will replace him? Do the Tories need a new Maggie to revitalise the party, or are they already on the road to recovery? Andrew Evans, Bletchley

I will be surprised if Michael Howard resigns as quickly as William Hague did after his disastrous showing in 2001. The party needs to take stock and work out how to turn themselves into a government-in-waiting. Mr Howard may agree to stay on until more of the groundwork is laid. It would be easier for them if their new leader was not chosen by a vote of party members - they have an average age of well over 60 and are not in touch with the electorate at large. They need a candidate in the American sense, preferably a youngish man or woman with a family who can make Gordon Brown look out of date. The most powerful slogan in politics is "Time for a change" and the Conservatives must position themselves so they can successfully carry the hopes of a new generation. They are beginning to make considerable progress. How can you tell? They have stopped being obsessive about Europe.

How quickly do you will think Tony Blair will stand down - and will the size of Labour's majority (assuming they win the election), make any difference to the timing of his departure? Matt Wilkinson, Suffolk

Tony Blair, like every other leader, is likely to stay for as along as he can. Very few politicians realise when the game is up. He has promised to stay on "for a full term" and it will be a test of Mr Brown's nerve if he can put up with endless talk of "will I, won't I?" from Mr Blair when the chancellor clearly wants to see the back of him as soon as possible. Because they have both openly swung behind the campaign this time, it is hard to see how this can be portrayed as anything other than a joint effort. I don't see that the size of the majority will make much difference. But my old colleagues in the Parliamentary lobby may well not see it that way: they've got to write about something when the election is over.