Andy Sawford, Labour's victor in the Corby by-election, repeated a well-worn line in his acceptance speech yesterday: that the road to Downing Street runs through his new constituency.

Indeed, Corby appears to be a bellwether seat. For three decades, the party that has taken Corby has gone on to form the next Government. However, Ed Miliband would be unwise to gloat over this result for various reasons.

First, Corby is far from being a classic "middle England" constituency. Rather, it is sharply divided between chocolate-box rural Northamptonshire villages and Corby, which retains a strongly Scottish character, thanks to the now-retired steelworkers and their families who flooded into the new town in the 1960s. In fact, it was some of these ex-patriots who recently campaigned for voting rights in the Scottish independence referendum.

Secondly, by-elections often throw up atypical results because voters tend to use them to cast protest votes, especially if they wish to punish a party for triggering an unnecessary poll. The decision of the Conservative, former chick-lit author Louise Mensch to stand down half way through the term for family reasons, undoubtedly had an impact on this contest.

Thirdly, local issues played a major role in the campaign, particularly the downgrading of Kettering General Hospital, which was exploited by Labour.

All in all, there were too many extraneous factors in this contest to draw any firm conclusions about Labour's recovery under Mr Miliband. Nevertheless, it was an impressive win. To turn a 2000-vote deficit in 2010 into a majority of close to 8000 on a lower turnout is more than a good result.

It is also one that creates a dilemma for the Coalition partners. The other candidate smiling broadly after the count was Margot Parker for the UK Independence Party, who won more than 5000 votes, or close to 15% of the poll. For David Cameron and the Conservatives the challenge is how to speak to those in the middle ground, who appear to be drifting back to Labour, yet prevent a haemorrhage of the Eurosceptic right-wing to Ukip. The Liberal Democrats' lost deposit speaks for itself.

The Prime Minister was content to put the result down to "mid-term cyclical politics" but at least it was a proper contest. That is more than can be said for the 41 elections in England and Wales to elect the first police and crime commissioners. Apathy and confusion appear to have been the winners in these polls, along with the dismal November weather. Though Home Secretary Theresa May continues to claim commissioners will be "the voice of the people", the appallingly low turnout suggests otherwise. Arguably, the old police boards, which have survived in Scotland and include elected local councillors, have greater democratic legitimacy. As the Electoral Commission said yesterday, the dreadful turnout should be a concern for everyone who cares about democracy.

Would the Government have been better off spending the £100 million this exercise has cost on recruiting 3000 more police officers?