The reputation of key politicians has been hit. The number of voters citing David Cameron as important in their decision has fallen from 34 per cent in May to 26 per cent now.

Only a third of Britons say Mr Cameron would be the best person to negotiate Britain's withdrawal from the EU as Prime Minister in the event of Brexit, though this is higher than anyone else.

In a blow for Chancellor George Osborne, his warning that house prices will be lower in the event of Brexit made people more likely to vote Leave than Remain – by 17 per cent to 20 per cent.

Last night a flurry of eve-of-referendum polls suggested the result is still too close to call, with TNS giving the Brexit camp a 43 per cent to 41 per cent advantage.

A YouGov poll for The Times gave Remain a lead of 51 to 49. FTI Consulting gave Remain the edge by 51.4 per cent to 48.6 per cent once 'don't knows' are taken out.

Boris Johnson gives a thumbs up as he leaves Selby, North Yorkshire, on a hectic day of campaigning

David Cameron spoke alongside Lib Dem leader Tim Farron at a Remain rally in Birmingham this evening

Opinium Research recorded a tiny lead for Brexit in its final survey of 3,000 voters this week as it found 45 per cent backed Leave and 44 per cent backed Remain.

But after taking into account the margin of error in the study, the firm declared it impossible to predict a winner.

A week ago, Opinium had the referendum tied at 44 per cent each while at the start of June the pollster had Remain ahead 43-41.

The poll fits with the mixed found by all of the polling firms in the last week of the race, with some results showing small leads for either side while other showed a tie.

By contrast, betting markets have continued to show Remain as the strong favourite as the race enters its final hours.

Adam Drummond, of Opinium Research said: 'This really is ''too close to call'' territory with undecided voters holding the balance of the vote in their hands.

'Although referendum campaigns normally see a move back to the status quo as we get closer to polling day, this hasn't yet shown up in our polls and the Remain camp will have to hope that it happens in the polling booth itself if Britain is to stay in the European Union.'

In its latest poll, Opinium interviewed 3,011 voters between Monday and Wednesday.

David Cameron was greeted by school children as his whistlestop tour took him to Bloxham near Banbury yesterday in his final push for votes before the referendum

Boris Johnson was mobbed as he took the Vote Leave campaign's final push to Selby in North Yorkshire