Legal proceedings over postal voting which could delay the general election are being launched in the High Court.
Postal vote applications have risen dramatically
Birmingham City Council's deputy leader John Hemming is seeking a judicial review of the postal voting system.
It comes after a judge found fraud was "widespread" in the 2004 local polls in the city. He also said there were no effective safeguards in place.
A huge rise in applications for postal voting in 5 May's poll has raised fears about potential fraud.
The main parties are accused of asking voters, especially in marginal seats, to send postal vote applications to them. But they insist the practice is within the rules.
The Electoral Commission code of conduct allows parties to send out and receive applications for postal ballots, but says activists should not handle the ballots themselves.
Mr Hemming, who is also leader of the Liberal Democrat group on Birmingham City Council and is standing in the Birmingham Yardley constituency, will ask a High Court judge on Thursday for permission to review the electoral procedures supporting May's general election.
He will ask the judge to rule that he has an arguable case which needs to go to a full hearing as a matter of urgency.
He said he was taking the action because of the "very real likelihood" that votes country could be rigged.
He claims the absence of a secure voting system breaches human rights by compromising the secret ballot.
Mr Hemming had a key role in raising allegations of local elections fraud in Birmingham in an elections court.
At the end of the case, election commissioner Richard Mawrey QC sacked six Labour councillors for vote rigging in two Birmingham wards and said the scale of fraud would disgrace a "banana republic".
Mr Hemming is calling for all postal votes cast at the 5 May election to be counted separately from non-postal votes.
He then wants political parties to be given permission to check application forms for postal votes and for the period in which election petitions can be raised to be increased from 21 days to two months.
According to the BBC's Political Editor Andrew Marr, the Conservatives have said they would support these changes to the system.
Shadow foreign secretary Michael Ancram said the way the postal vote registration system had been relaxed had left it open to abuse.
Police chiefs are due to meet senior civil servants to discuss arrangements for the general election - amid concerns about postal voting fraud.
The talks on Thursday are being chaired by the most senior civil servant in the Constitutional Affairs Department and will bring together representatives from the Royal Mail, the Association of the Electoral Administrators and returning officers.
The Royal Mail has predicted that around 6.5 million people will vote by post, around 15% of the electorate. In the last general election in 2001 only 2% voted by post.
Society for Local Authority Chief Executives and returning officers' leader David Monks said the late availability of postal votes made it impossible to check them all.
"There has been an explosion in postal vote applications and it does present us with some difficulties."
He said cases of 20 or 30 postal votes going to the same address and streets where 80% of residents were getting postal votes were being seen.