The average opinion poll figure showed Labour, with a 22.5 per cent lead, had slipped 2.5 per cent compared with May, but surveys by NOP in the Sunday Times and Mori in the Times this week show a 6 per cent drop over the month.
Analysis by Mori suggested the Tory boost could have resulted from a "feel-less-bad" factor after England's soccer triumphs against Holland and Spain. But the evidence from this week's council by-elections shows little sign of a plunge for Mr Major after Wednesday's defeat by Germany.
A projection of 21 comparable results over the month, covering more than 30,000 votes cast, puts Labour ahead by 14.5 per cent, down from 16 per cent in May.
The figure is almost identical for the seven contests that took place last Thursday - despite three Labour seat gains.
The latest indicators put Conservatives above the psychologically important 30 per cent support nationwide.Reuse content