Brown had been furiously campaigning after a rallying speech on Monday appeared to galvanise the Labour support.
But less than 24 hours later – typical of an election campaign that has at times descended into farce – his comments were overshadowed by “maverick” Labour candidate Manish Sood, who spent much of the day calling for Brown to apologise “to the people and the Queen”.
Labour publicly played down the incident, with campaign co-ordinator Douglas Alexander dismissing the candidate for Norfolk North West as “eccentric”. However the party was furious behind closed doors that another gaffe could have unravelled the climax to its campaign.
Brown had spent the day in Warwick with actor Ross Kemp after appearing on the GMTV sofa with his wife Sarah.
Both the Tories and Lib Dems slammed Ed Balls after he urged Labour supporters to vote tactically to block Lib Dem seats.
David Cameron, campaigning in north London, said the message proved what he had been saying all along: “If you want to keep Gordon Brown in Downing Street you vote Lib Dem”.
Shadow Defence Secretary Liam Fox said the plea “smacks of political bankruptcy... the sort of old politics that people hate.”
In another blow to Brown, Nick Clegg made sympathetic sounds over the prospect of talks with the Tories – something that has left both sides cold throughout the campaign.
Clegg said a Tory government would struggle to push through the necessary change without dealing with the other parties. He even said electoral reform is not a precondition for the sides entering into talks.
Meanwhile online bookmaker Paddy Power agreed to pay out £100,000 of bets placed on a Tory victory. The bookie said the odds had been slashed so far they would pay out bets placed before last Monday.
The markets, however, were not so sure. The pound dropped to a fresh one-year low against the dollar as uncertainty over the election result heightened. Investors fear a hung parliament will prevent the drastic spending cuts the economy needs.