THERE can be few more varied constituencies in Scotland that Cunninghame North, which sweeps from one area of high unemployment on the Ayrshire coast through the comfortable towns of Largs and Wemyss Bay to the depressed Garnock Valley.

Yet each of the main contenders is confident that they can persuade the diverse electorate that not only are they the person best qualified to represent the interests of North Ayrshire but that their party has the best solutions to the problems which exist.

It is never easy to predict how such a mixed cross-section of voters will perform when inside the polling booths but what is certain is that Mr Brian Wilson is taking nothing for granted, despite a majority of almost 3000 and a high profile, both locally and nationally.

Nor should he. For with little more than three percent of a swing required to give the Conservatives victory, his seat is Labour's most marginal north of the border.

His opponents will be making much in the coming weeks of the Labour ''fast track'' which Mr Wilson appears to be on - having held important shadow posts in transport and defence, he has emerged as one of his party's key figures in election strategy and planning.

The electorate will be asked to decide whether their MP can combine his constituency work with, at the very least, a junior ministerial role in a new Labour Government.

It is perhaps significant that he has chosen to answer the question in advance by his high-profile involvement with important local issues such as the dereliction of Largs railway station and the threatened closure of the historic garrison at Millport.

Mr Wilson: said: ''I have never been far from the local issues no matter what has been happening elsewhere and it is my intention to continue that close involvement after the election.

''There is a wide range of issues in my constituency from the local ones like the station at Largs to the more national ones like unemployment, which obviously are important to the people of the Garnock valley and of the three towns of Ardrossan, Saltcoats, and Stevenston. I have made it clear that I am not convinced by the performance of Enterprise Ayrshire in my constituency and I will be continuing to move towards persuading them to do more.

''At the same time, I believe that we have the policies to tackle unemployment and to bring prosperity to areas which have already waited too long.''

Mrs Margaret Mitchell spearheads the Conservative challenge and plans to ensure that she does not fall into the trap which appeared to ensnare former MP, now MEP, Mr John Corrie of ''working too quietly behind the scenes''. She said: ''I believe that John Corrie was a good constituency MP who suffered from a failure to broadcast the depth and success of his work widely enough.

''He paid the price. I also believe that we suffered in 1992 from the late withdrawal of Donald Findlay who was conducting a strong campaign.

''We will have neither of these problems this time and I feel confident that we can sway the soft voters, unconvinced that Tony Blair's interest in Scotland is genuine, to the Conservatives.''

For the SNP, Ms Kim Nicoll has picked up the theme of the perceived lack of Mr Blair's conviction from some voters.

She said: ''I have been picking up the message that while people may be fed up with the Tories they are not certain that their votes should go to Labour.

''My first priority has to be to secure what is a significant SNP vote and to ensure that these voters are happy with what they are hearing. Then the work starts on convincing voters in what is a diverse area, from the islands of Arran and Cumbrae to the former steel towns of the Garnock valley, that we are offering the best alternative.''

Ms Karen Freel for the Liberal Democrats is convinced that she can do well in the constituency by the use of a potent if not widely used political weapon - honesty.

She said: ''I will be telling the electorate that we will put up their taxes but at the same time tell them how the money will be spent improving education and the health service.

''Show me another party who take such an honest approach to taxation as we do. In addition, I plan to campaign on issues which may seem unimportant to the national pundits, like Largs station and road access to the RNAD at Beith but which are important to the many hundreds of people affected and should form a large part of what a constituency MP should concentrate on.''

The contenders

Labour: Brian Wilson, 48, won the seat for Labour in 1987. He has combined his parliamentary duties with journalism and is a regular contributor to The Herald and other leading publications.

SNP: Kim Nicoll, 37, represents Galston on the new East Ayrshire Council, previously she had spells on Kilmarnock and Loudoun District and Strathclyde Region.

Liberal Democrat: Karen Freel, 27, is a secretary with a property development company in Glasgow.

Conservative: Margaret Mitchell, 44, is a former teacher and qualified lawyer who has been concentrating on preparing to contest the seat since being selected in September 1995.