It will be a personal blow to the Prime Minister and increase the Government's difficulties when its majority of 21 is under pressure. The Liberal Democrats have a strong local government base in the Berkshire constituency.
Mr Major said he was 'deeply upset' by the death of Mrs Chaplin, 53, a close confidante. She was elected in the general election with a majority of 12,357.
Mrs Chaplin, a former head of the Institute of Directors policy unit, became special adviser to Nigel Lawson, the then Chancellor, in 1988. She stayed when Mr Major took over in 1989 and became his political secretary at 10 Downing Street.
She died at St Mary's Hospital, Paddington, from what are understood to be complications arising from a blood clot after an operation.Reuse content