Campaigners against voting reform in Gove mistake
Campaigners against changing the Westminster voting system have wrongly included Michael Gove on a list of politicians supporting their cause.
Those opposed to replacing first-past-the-post named a list of high-profile Labour and Conservative politicians who they said would back their campaign.
But they were forced to remove the education secretary's name after his advisers said he was "undecided".
Both sides are mobilising support ahead of an expected referendum on 5 May.
The coalition government has promised a public vote on whether to replace the current system of electing MPs with the Alternative Vote (AV) model.
The No to AV campaign published a list of senior politicians whom it said would help to advise on strategy and act as spokespeople, saying they demonstrated the cross-party nature of its approach.
Those involved include veteran Labour politicians Margaret Beckett, David Blunkett, Lord Falconer, Lord Reid and Lord Prescott and Conservative Cabinet ministers William Hague and Ken Clarke.
But Mr Gove's name was withdrawn after his advisers said he had never been "involved" in the no campaign and had yet to make up his mind on the issue.
They blamed a "misunderstanding" for his inclusion on the list.
However, the No campaign has stressed that Mr Gove has publicly endorsed the existing first-past-the-post system in TV interviews as recently as May.
As the two sides seek to raise the profile of their campaigns, Mr Blunkett, a former home secretary, said he would not mind campaigning alongside the likes of William Hague and Ken Clarke.
"We are the people with the experience over a lifetime in politics," he told the BBC News Channel.
"That is why we are joining together to say 'If there was something desperately wrong with our present system and if there was an alternative that provided all the answers that people want then by all means let's consider a change but we are not'.
"We are talking about a system that does work being replaced by an unknown system that could distort completely the votes of those who have the temerity to actually vote from one of the two major parties."
But those supporting voting reform said their opponents were stuck in the past.
"The people backing this campaign come from a bygone era," said Jonathan Bartley, from the campaign group Yes to Fairer Votes.
"An era of two parties where there was a narrow range of issues and people trying to influence a very small number of voters. Those days are gone.
"Now we have three parties, possibly more, and a much wider range of issues. We need a new voting system to reflect that."
AV is currently used in a wide range of elections including the recent contest for the Labour leadership and last year's ballot for the Speaker of the House of Commons, he added.
Deputy Lib Dem leader Simon Hughes said: "You should really not listen to people who are just defending a system which did very well for them but very badly for the public."
The Conservatives and Lib Dems agreed to hold a referendum as part of their coalition deal but Prime Minister David Cameron and his deputy Nick Clegg are on different sides of the argument over the need for change.
David Cameron has indicated he will campaign against reform, insisting that the current system is the best way to provide stable and accountable governments.
But Nick Clegg says the current system disenfranchises many voters and is not "fit for purpose".
Labour leader Ed Miliband has suggested he will campaign for a switch to AV but is opposed to holding the referendum on 5 May, the same day as devolved elections in Scotland, Wales and Northern Ireland.
Among other Labour politicians thought to favour a switch to AV are Alan Johnson and David Miliband.
Margaret Beckett, the former Labour foreign secretary who has become president of the No campaign, acknowledged there were differences of opinion within her party about the issue.
"He [Ed Miliband] is one of the many people, there are lots in all of the parties, who do see the attractions of an AV system," she told the BBC News channel. "I do not share that view. Ed knows I do not share that view... I do not regard that as a problem."
It is not clear what role the party leaders will play in the referendum campaign, with suggestions that the two camps want non-political figures to take the lead in trying to engage the public.
MPs have approved plans for the referendum date despite concerns that combining it with devolved elections will detract from these polls and potentially confuse voters.
Peers are currently debating the bill paving the way for the referendum.