Is Bradford East, the seat held by Labour since the by-election of November 1990, about to go west to the Liberal Democrats?

After two of the three party leaders’ TV debates, the polls are still showing a stronger rating for Nick Clegg than they were at the start of the campaign.

But though he appears to be top of the pops on the box, that does not necessarily mean the Liberal Democrats will win the General Election, with the personable Mr Clegg as the next Prime Minister.

Nina Reynolds, Professor of Marketing at Bradford University’s School of Management, said: “In polling you are asking for people’s future intentions. Those intentions may change.

“Opinion polls are historic. They ask lots of questions, then collate the answers and report them. By the time the answers are reported, the answers are ‘old’ – even if it is only by a couple of days.

“What we have seen is that the first TV debate had an impact on the poll, and that Nick Clegg has so far coped best with that environment.

“In our first-past-the-post voting system, because a party leader has a certain degree of polling support doesn’t mean people will vote for that person in an individual constituency.

“A small change of opinion in a constituency can make a huge difference.”

Especially in Bradford East, where Liberal Democrat candidate David Ward hopes to overturn the 3,511 majority of Labour stalwart Terry Rooney.

There is no definite correlation between dramatic national polling samples and what happens in particular constituencies – a point made by Nina Reynolds and emphasised by Bradford political researcher and author Richard North.

In 1997, Richard was a Referendum Party prospective parliamentary candidate; in 2001 he was a UKIP election agent in Bradford South and Bradford West, and in 2005 he worked for the Tories.

He said: “What makes this election both frustrating and impossible to read is that the polls are structured to measure the swing from one party to another. They are not constructed to deal with a multi-party context; particularly, they cannot take account of local effects at constituency level.

“Speaking to people in the pub and the shops round here (he lives in Wibsey in Bradford South, held by Gerry Sutcliffe with a 9,167 majority) the number one issue is indifference. You don’t get the feeling there’s an election on at all. It’s a safe Labour seat and the Tories have given up anyway.

“To a seasoned observer it isn’t polling or sampling that counts, but the mood of voters. Polls are incredibly bad at testing whether people are going to go out and vote.”

Colin Mellors, Professor of Politics and Pro-Vice Chancellor of York University – posts he formerly held at Bradford University – said the fate of Bradford West (Labour with a 3,026 majority), Keighley (Labour, with a 4,853 majority) and Shipley (Tory, with a 422 majority) could depend on three factors.

“The Clegg effect and the Liberal Democrat surge; tactical voting, and local issues such as the personal vote that Ann Cryer may have had at Keighley,” he said.

“Until last week, the polls were static, giving the Conservatives a clear lead. That’s changed, of course. Polling is an inexact science, as was demonstrated in 1992 when the polls were eight points adrift in their predictions and John Major won.

“There would have to be swings of 0.5 per cent in Shipley for Philip Davies to lose, probably to Labour; a four per cent swing in Bradford West, for Marsha Singh to lose to the Conservatives, and a five per cent swing in Keighley for Labour to lose, probably to the Conservatives.”

Voting for another party to get what you want, usually the removal of a sitting candidate, is impossible for pollsters to measure. There is another problem too, as Mr Mellors explained.

“There are huge regional variations. There is a swathe of seats – from Leeds to Bradford, the Calder Valley to Manchester, down to the West Midlands – where the Tories have to make gains. This is their key battleground. For Labour and the Liberal Democrats, it’s the South-West.

“A small Liberal Democrat surge is more damaging to the Conservatives than to Labour: that may be Labour’s best hope.

“With the mid-point of the campaign reached, polls still suggest that leadership appeal, rather than policy content, is winning over undecided voters.”

The fate of seats, especially Bradford East, Bradford West, Keighley and Shipley, may turn upon the outcome of next Thursday’s debate on the economy.