Conservative lead back up to six

Voters also expect David Cameron to perform best in the leaders' debates.

The Conservatives have extended their lead over Labour but Britain remains on course for a hung parliament at the election, according to a new poll. The latest Sun/YouGov daily survey put the Tories up one point to 38 per cent, Labour down one to 32 per cent and the Liberal Democrats up three to 19 per cent.

If repeated at a general election on a uniform swing, the latest figures would produce a hung parliament with David Cameron 39 seats short of an overall majority. The Tories would have 287 seats, Labour 285 and the Liberal Democrats 48.

The poll also found that voters expect Cameron to perform best in the forthcoming leaders' debates. Forty two per cent of those surveyed said Cameron would come out on top, compared to 16 per cent for Brown and 11 per cent for Nick Clegg.

Twenty seven per cent of the public said they were certain to watch the televised debates, with 40 per cent saying they were fairly likely to watch them and 12 per cent saying they would not watch them.