Michael Howard fiercely attacked the Government today over its failure to protect the postal voting system from potential fraud.

The Tory leader said that Tony Blair should be "thoroughly ashamed" of deciding to ignore a watchdog’s call for tougher measures to prevent abuse. He accused ministers of rejecting the advice of the Electoral Commission because their recommendations would have hit Labour votes harder.

A survey by The Times revealed today that applications for postal votes have soared by up to 500 per cent in marginal constituencies, as eager party activists hand out application forms to voters and offer to collect them and drop them in the post.

The Electoral Commission has recommended that the parties stop doing this, but the Government has failed to take action to ban it.

At a press conference, Mr Howard alleged that the Commission’s recommendations had been accepted as high up as a Cabinet committee, "but that when it was appreciated that certain categories of voters particularly favourable to the Labour Party might be less inclined to vote... the recommendations were ditched."

He said: "I think it’s a scandal and Mr Blair should be thoroughly ashamed of what he has done to our democracy. If we had had our way, the recommendations would have been accepted and implemented and we would not have a voting system fit for a banana republic, which is what the High Court judge said is the present position."

But he came under attack in his turn because Tory activists are doing exactly the same thing.

The Times survey showed that applications for postal votes have almost trebled overall since 2001, when the rules restricting who was eligible were relaxed.

In Cheadle, Manchester, where the Liberal Democrats have a majority of 33, the number of applications stands at 8,226, nearly five times the 1,695 cast in 2001. In Dorset South, where Labour has a wafer-thin 153 lead, applications have increased to 192 per cent of 2001 levels.

Other marginals showing large increases in applications include Labour-held Thanet South, Rugby & Kenilworth and Braintree, Lib Dem-held Mid-Dorset & North Poole, Norfolk North and Weston-super-Mare, and the Tory-held seats Taunton and Orpington. Southampton has seen a 13-fold leap from 2,000 to 26,189 while Basingstoke has recorded a sevenfold jump from 1,500 to 11,375.

Election officials privately blame the surge in postal voting in marginals as evidence that the parties are organising for people to register. Most expect a further surge nearer to polling day.

The figures coincide with mounting concern about the aggressive way in which all three main parties are trying to maximise postal votes. The Tories and Labour are processing millions of applications sent to freepost addresses in Dartford and Newcastle, before forwarding them to returning officers.

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