It's the Conservatives' internal divisions which will scupper them in 2015

Elections are adversarial - they are a clash between alternative ideologies and, above all, personalities. There was not much wrong with the Labour manifesto in 1992 but there was no way that the country was prepared to have Kinnock as Prime Minister. Five years later John Major, a decent if uninspiring leader, was swept away by the youth, intelligence and carefully stage-managed appeal of Tony Blair. In 2010 the Kinnock effect returned to oust Gordon Brown who many felt had no right to be Prime Minister anyway. But the Tory Manifesto wasn't the winner. Those who were suspicious of it, but had had enough of Gordon, leaned in the "I agree with Nick" direction and gave us a hung Parliament and that led to the shambles of Coalition. 

Analysis of the failure of the Coalition has again to be seen in an adversarial context as well. Labour, as a Party, is comfortably leading in the Opinion Polls, but there is a sense of "by default" about this. Can you name ONE policy that Labour has that has strong popular appeal? Their broad proposition is that they are nicer than the Tories (which they probably are), more caring (likewise) and potentially more competent (much more questionable). Seeing this many Conservatives look to play the "personality" card to save them. Hence the renewed affection for Boris who is the stand out politician of the times not because of his policies (fluffy and confused) his record (patchy at best in a job that is pretty lightweight anyway) his character (he's a bit of a shit) - but because despite all this people like him. In an "X Factor" society he's the one that has it.

If David Cameron had a united Party behind him he could be a formidable electoral asset for the Conservative Party. If most Tories were promoting the Cameron brand rather than undermining it and seeking alternatives then the Party would be far more appealing. Most people aren't too bothered by the minutiae of policy proposals. UKIP, a shallow and prejudiced bunch of Golf Club bores, has short-term appeal because it has two policies (on Immigration and Europe) which have resonance with a significant minority of the electorate. Ed Milliband seems to believe that a carefully worked out Manifesto which shows Labour to be trustworthy and potentially competent on managing public finances will secure victory. I rather doubt this.

Divided parties don't win elections. The more the Conservatives tear themselves apart the less likely they are to win anything in 2015. My guess is that Labour, despite having a leader who lags behind his Party in appeal and despite the likelihood of that leader being beaten on the hustings by the Prime Minister, will win a working overall majority in the General Election. Echoes of 1979 when Thatcher was less popular than Callaghan personally but could present the "Labour has failed" message to good effect.