There is no doubt that the forthcoming by-election in Eastleigh will be a two-horse race.
Ed Miliband and Labour know that the best they can hope for is to avoid the humiliation of coming fourth behind UKIP.
But David Cameron could very well pay the price for his support of gay marriage - which clearly has infuriated many of his backbenchers and Tory activists. And coming so soon after the ignominy of Britain losing its AAA-rating, the vote will be crucial in guaging the voters' verdict on George Osborne's handling of the economy thus far.
Up until now, polls have suggested that the Tories are ahead of Labour on who voters trust to handle the economy and that the electorate still blame the previous government for the current economic climate.
But Peter Kellner, head of polling company YouGov, speaking on the BBC this week, has intimated that the downgrading of Britain's economy could signal a 'blame-changer' and a turning-point in voters' perceptions of who is responsible for this country's continuing financial woes. http://dominicavibes.dm/news/uk-loses-top-aaa-credit-rating
After all, three years into this parliament, it is frankly lame for the Tories and the Liberal Democrats to keep harking back to the economic mess they had to clear up on coming into office. On Labour's departure in 2010, Britain was slowly starting to come out of recession and the current administration's strategy of making huge cuts in public spending at such a furious rate, has certainly not worked, with the UK entering a double-dip recession under their watch, and a third dip in the economy still very much a possibility.
And now, with Britain being stripped of their AAA rating, this could very well be reflected in the outcome of the Eastleigh by-election. It is just possible that its voters may reject the Tories' message and stick with the Liberal Democrats, who have held the seat since the bizarre death of Conservative incumbent Stephen Milligan in 1994.
On the other hand, the news that Liberal Democrat leader and Deputy Prime Minister Nick Clegg is now embroiled in a sex scandal could be very damaging for his party's prospects in Eastleigh.
The by-election was caused by the resignation of former Cabinet Minister Chris Huhne, who was forced to stand down following his conviction for perverting the cause of justice. He has pleaded guilty to charges that he persuaded his former wife, economist Vicky Price, to take his penalty points for a speeding offence in 2003.
Mr Huhne is now almost certainly facing a period in jail when he is sentenced in the coming weeks.
But to compound the embarrassment for the the Liberal Democrats, questions are now being asked about how much Mr Clegg knew about allegations of sexual harrassment levelled against the former Party Chief Executive Lord Rennard.
A Channel Four News investigation has revealed that, prior to his retirement on health grounds in 2009, the Party received complaints that the veteran peer had made improper sexual advances towards several female party workers.
Lord Rennard has strenuously denied any wrong-doing.
But is alleged that both Mr Clegg and Vince Cable, now Business Secretary, were made aware of the claims at the time. And the revelations have raised questions about internal disciplinary procedures within the Liberal Democratic Party machine.
However Mr Clegg's office is insisting that he and Mr Cable only gained knowlege of the Rennard affair when recently approached by Channel Four.
Even if the Lib Dems do hold on to the Hampshire seat, the breaking of this story just days before the voters in Eastleigh go to the polls, is hugely embarrasing for Nick Clegg.
And it is likely to run for some time yet.