Ed Miliband launches Labour's new year offensive today by laying into the big four banks and their bonuses. On Monday, the shadow work and pensions secretary, Rachel Reeves, will make her first policy demarche on jobs and pay. More follows soon on education, housing, childcare, the living wage, NHS, party reform and big infrastructure.

Sixteen months to go there is still much convincing to be done on Labour's two great contradictory electoral essentials – to win confidence as credible managers of the economy and to breathe excitement into the prospect of a Labour government. They are not there yet.

Labour's past still hangs heavily, as it fails to reclaim what was done best in those 13 years while refusing to admit enough errors. But that's why oppositions seldom return after just one term. The past dogs some in the party too, fondly dreaming the tactics of 1997 could win again, if only they stay close to the wind of Tory deficit reduction plans. Again, today, Miliband rejects the Tory-lite option. If he can't convince voters that the economy is seriously awry for future growth and for ordinary incomes, why would they choose Labour?

Plainly, he is making headway: why else would the ultra-political George Osborne snap out his wish to raise the minimum wage on the eve of this speech? Miliband has hammered out from the start his critique of a system that delivers for the top few while squeezing everyone else. He ignited indignation at the warped energy market and now returns to the abominations of banking where so little has changed. How egregious are their sins, yet how little personal penalty was paid despite Libor-rigging and mis-selling useless products to trusting customers. Instead, the Bank of England has quantitatively eased riches into its vaults, which it refuses to lend to cash-starved small businesses.

There is a world weariness about the bank bonus scandal, as if that stratospheric realm is too far beyond the imagining of most voters. How can there be more bankers earning in excess of £800,000 in Britain than in the entire EU? Barclays pays more people £1m than the entire Japanese corporate sector. The ever watchful High Pay Centre dubbed it Fatcat Wednesday last week when FTSE 100 CEOs earned as much in their first two and half days back at work as average earners get in a full year, bankers at the pinnacle. In 2009, Osborne pretended to agree when he famously said: "It is totally unacceptable for bank bonuses to be paid on the back of taxpayers' guarantees. It must stop." Instead he's fighting an EU bonus cap of 100% of salary. These sums are not just disgusting, but set a stamp of approval on the risk-taking avarice of the wolves of Wall Street and the City. The British Bankers' Association protests bonuses ensure payment is only for results, claiming delaying the booty for a few years dampens down the fever, though no one expects funds to be clawed back.

This remains fertile Labour territory, the epitome of the "predatory capitalism" Miliband first dared denounce. Today he fleshes out what he means by responsible capitalism as he sets about "vested interests" and "short-termist broken markets" with their "race to the bottom" in pay for the rest. His cost-of-living crisis isn't just about a temporary gap between pay and inflation: even if pay starts to catch up, the dysfunction is structural and permanent – insecure jobs, insecure housing, families well above the middle worried for their children, and a third of graduates with debts and low-paid jobs. Miliband challenges how the country is run and "who it's run for". Average figures may show growth – but averages are mendacious. The only month since 2010 when "average" pay didn't fall was a month when bankers' bonuses distorted the average. "Average" should be banned by the ONS when mega-wealth disguises most people's reality.

Expect a torrent of Red Ed abuse to follow what will be quite a radical speech. No surprise the Bank of England governor, Mark Carney, got in his attack before the speech was made. Even if unemployment dips down to 7%, don't expect him to be anything but political in raising interest rates: whatever his "forward guidance", he won't do it before the election.

When Miliband ventured this week into the hostile turf of the Telegraph's pages to warn that their "middle class" is squeezed too, the push-back was a salutary reminder of the forces arrayed against Labour in a spray of venom from all the Tory press, plus the usual ragged platoon of ex-Labour Miliband ill-wishers. He plainly touched a raw nerve by showing Labour is talking not just about what one wag called "the squeezed bottom", but the 85% who earn under £40,000 – a figure the Telegraph newsroom and most Tory backbenchers fail to factor into their idea of a "middle class", which is the rather smaller 7% using private schools and healthcare.

Slipping in the polls as the good economic news flows in, Miliband's best chance is to say what he means and mean what he says, as he will today. Experimenting with a sober style at PMQs has been painful this week, with most commentators saying he was trounced by the cheap jokes and vulgar abuse of his opponent. But if he dare keep his nerve, red-faced Etonian bullying and bellowing may come to look undignified in a prime minister. William Hague did well in that loathsome pit, but much good it did him.

Ed Miliband is not the best salesman of his ideas, is no orator, and is short on showmanship, with a mildly eccentric manner. (Attlee, Heath and Major lacked obvious charisma too, and "best leader" is less important to voters.) He will win if his ideas chime with enough voters, or at least if he can frighten enough people with the prospect of a second Tory term. Labour fears being the "welfare party" but the Tories have as much to fear as the "wealth party".

History is a poor guide to victory in 2015, as on precedent neither side can win: parties in power don't increase their votes, but parties trailing on the economy and best leader rarely win either. One or other of these will be false. Honest conviction is Miliband's asset – but he looks a bit lonely. It would help if more of his team were out there thumping the same tub. Ed Balls and some others seem to hang back on denouncing the profound dislocation of Britain's unproductive and unjust getting and spending of national wealth. Too many of them are stuck in a 1997 time warp, yearning to reprise the politics of a lost era. This time there is no safe option. With growth returning, only a frontal assault can turn people against the complacent and inept nastiness of Cameron and Osborne economics.