Ed Miliband was handed a Get Out of Jail card yesterday by none other than one of the Big Six energy companies.

And my goodness did he need it. His personal ratings had plummeted after a poor response to the Budget last week followed by a pedestrian speech to the Scottish Labour conference in Perth - he should get new advisers on Scotland - then a tranche of Labour-friendly commentators and think tanks fired a shot across his bows demanding boldness on Monday.

Not often do the markets bring good news for Labour but that indeed was the case yesterday morning when they opened five hours before the looming bout with the prime minister in the House of Commons.

None other than SSE, the second biggest energy supplier in the country, announced it would freeze domestic power prices at their current levels until 2016. For Mr Miliband the timing was impeccable. It allowed him to go on the attack, get the cost of living issues back to the top of the agenda and claim credit for putting pressure on the Big Six. David Cameron would have had to rewrite his script, it was not going to be the rout he might have anticipated.

Cost of living issues matter and, however often Mr Cameron tries to say otherwise, living standards will be lower at the time of the General Election in 2015 than they were when Labour left office in 2010.

Wages will not have caught up with prices, food banks will not have disappeared and housing costs will continue to rise. Even after the recent Budget the OBR said people would still be saving less than they expected and personal debt would continue to rise.

But to win the election Mr Miliband will have to win arguments on the economy. When James Carville, Bill Clinton's strategist declared "it's the economy, stupid" he knew what he was talking about. Workers, families, pensioners, businessmen and women will vote for the party they think most likely to improve the quality of their lives.

Mr Miliband's team believe cost-of-living issues and the economy are binary, sort one and you'll sort the other. What they are less robust about is how they will tackle the deficit - and for that matter neither are the Government.

The Labour government was not responsible for the global financial crash but they were there when the music stopped and have paid a heavy price. While Labour walked off the political park to conduct a lengthy leadership election, the Tories and Liberal Democrats made hay, successfully pinning the blame on Labour. Labour lost any credit for maintaining growth in the economy and bringing down unemployment in the immediate aftermath of the worst financial crisis for nearly 100 years. And they have failed to make up ground. Until they do it is unlikely they will make headway in the polls.

Mr Miliband needs to resolve whatever differences he has with shadow chancellor Ed Balls, get on to the front foot and set out a positive economic vision.

He is persuading voters he is on their side but as the most recent polls show he is far from persuading them he is up to the job of prime minister. And that is his policy dilemma: because he has so little personal capital, radical policies may be out of the question. Instead he may have to concentrate on convincing the voters he is a safe pair of hands.

Mr Miliband would be greatly helped if he had a more energetic shadow cabinet. It's a safe bet most voters could not name half of them and, although the same could be said for the cabinet, the shadow cabinet needs to be hungrier, desperate to get into office.

But whatever Mr Miliband's present travails, he is very much still in the game. The electoral arithmetic makes it as possible for the Labour leader to get the keys of No 10 as it does for Mr Cameron to keep them. The LibDems have lost votes mainly to Labour, while the Tories have lost votes to Ukip in England and the SNP in Scotland during the last 20 years.

Between now and May next year Mr Miliband will be trying desperately to hang on to disaffected LibDem supporters who have come over to Labour and Mr Cameron will be on a charm offensive to hang on to disaffected Tories. There is much to play for.