CONTROVERSIAL plans to hit drivers across Greater Manchester with congestion charges could see Transport secretary Ruth Kelly lose her Bolton West seat, a new survey suggests.

A poll of voters in her Bolton West constituency revealed that 76 per cent of people said they were "very" or "quite" unlikely to vote for Ms Kelly in a general election if road charging was introduced.

She will defend a majority of 2,064 at the next election, facing Trafford council leader Susan Williams, who will be the Conservative candidate and an as yet unnamed Liberal Democrat.

Ms Williams' council has already voted against submitting a £3bn bid to the government's Transport Innovation Fund - which would trigger a local congestion charge of up to £5 a day at peak hours.

However, the bid still went in because of the votes of a majority of councils in Greater Manchester.

Aspect Market Research carried out the telephone poll of 300 people, half in Bolton West and half in other parts of Bolton.

A total of 77 per cent said they did not agree that improved public transport should be funded by congestion charging.

And 61 per cent of people who voted for Ms Kelly at the last election in 2005 said they were 'very' or 'quite' unlikely to vote for her again.

The poll was commissioned by the Federation of Small Businesses.

The new poll came as Ms Kelly told the Labour conference that a pay-as-you-drive road network was ultimately 'inevitable'. She said the economic cost of congestion would eventually force the government's hand.

"Ultimately some form of road pricing is inevitable," she said.