George Galloway yesterday called for "the mother of all by-elections" to be held in a Birmingham constituency following claims that the contest was marred by vote rigging.
The controversial Respect Party leader called for a re-run of the General Election contest for Sparkbrook and Small Heath during a party rally in Birmingham.
Salma Yaqoob, the Respect candidate who helped cut Labour MP Roger Godsiff's 16,246 majority to 3,289, has lodged a petition with the High Court alleging that widespread fraud took place during the contest.
Mrs Yaqoob plans to present evidence demonstrating how people who arrived at polling stations to vote were turned away because someone had applied for and used a postal vote in their name.
Others attempted to vote only to be told that someone else had already voted in their name, Ms Yaqoob claimed.
Mr Galloway recently said Tower Hamlets council in London "disgraced a banana republic" for its handling of the poll in Bethnal Green and Bow, where he defeated Labour's Oona King.
Turning his attention to Birmingham, Mr Galloway said yesterday: "This is the original banana republic, according to the election court."
The MP said his party was growing "exponentially" and he considered Birmingham to be his "number two base".
He said: "Of course, we hope there will be the mother of all by-elections if the legal case is considered and the court finds Roger Godsiff's success to be gained from a deeply flawed election.
"A Salma Yaqoob verses Roger Godsiff by-election would be heaven sent."
The rally, held at Birmingham Sport Centre in Highgate, saw more than 600 Respect followers listen to a speech by Mr Galloway. It was the first party rally in the city since his election victory.
The Sparkbrook and Small Heath constituency includes Bordesley Green, where an election court earlier this year found three Labour Birmingham city councillors responsible for conducting a campaign of postal vote fraud.
The three were expelled from the council and 19 Labour supporters were also named in court as having taken part in corruption. Mrs Yaqoob said: "We are still waiting to hear from the court since we made the application.
"However, we thought it was the right thing to do as we have specific examples of people who could not vote when they wanted to.
"The system is widely open to abuse - that is something that has already come out of an election court held here in Birmingham."
Mr Godsiff, who denounced postal vote fraud in a speech to the House of Commons shortly after the June 2004 council elections, has already made clear his suspicion that malpractice may have occurred during last month's General Election.
Mr Godsiff said: "There have been people who have come here and been told that they have got a postal vote. Also a lot of postal votes appear not to have reached people. People are being denied the right to vote and this is a cause for concern and should be investigated."