As Barack Obama prepares for his second inauguration in front of the Capitol building on Monday, most politicos are by now familiar with the demographics which helped put him there. Election night saw 96 per cent of African-Americans vote for the President; 70 per cent of Hispanics and 73 per cent of Asian Americans. Less dependent on traditional independent voters, the Democrats 'expanded the electorate' by boosting turnout in these communities.

That this causes a problem for the Republicans has quickly become conventional wisdom. It's been little noted, though, how the demographics of 6 November create a challenge for the Democrats too. An important component of the Obama campaign's "get-out-the-vote" (GOTV) effort was the President's personal appeal. There was a pronounced sense of a personal connection between many non-white voters and Obama, and of protectiveness (of which race was one but not the only factor).

The question for 2016 is, how do the Democrats maintain that level of support without Obama on the ticket? They are unlikely to find a candidate with the charisma, backstory and platform to match Obama, whose breakthrough was a truly once-in-a-generation event.

The answer can only be that, from the White House to the Senate, Democrats need to go further in the next four years to deliver on substance for these communities. Here, immigration reform is often mentioned. But just as pressing is the indelible link between race and poverty in America, particularly in urban areas.

Far too many of the majority black neighbourhoods that helped deliver Obama's re-election in states like Virginia or Ohio continue to be blighted by hardship. A litany of grim statistics bears this out. More than 1 in 4 African-Americans and Hispanics grow up in extreme poverty - with millions struggling just above this threshold. Forty per cent of children in African-American communities grow up below the poverty line (the US is ranked 34 out of 35 of industrialised countries when it comes to child poverty). Poverty is not of course simply an ethnic minority issue – but they are clearly disproportionately affected.

None of this is new. The statistics are familiar, and wash over many American heads by now. But as Michael Harrington once wrote in his seminal book on the subject, The Other America, "you can rationalise statistics...but you cannot rationalise an indignity". Nearly fifty years after Martin Luther-King said that "I have the audacity to believe that peoples everywhere can have three meals a day for their bodies, education and culture of their minds, and dignity, equality, and freedom for their spirits", a significant chunk of the US is still held down by hunger, violence, illness, poor education and precariousness. And sadly, that number has increased since 2007.

Anyone going door-to-door in the election in some of the poorer parts of places like Franklin County in Ohio would have found many who benefited in some small way from the President's first term. Particularly so on healthcare. Stimulus spending and his general stewardship of the economy have also stopped a total collapse in living standards. It could have been a lot worse.

But, as the likes of Paul Tough have argued brilliantly, this is not the prospectus on poverty that Obama the candidate first emerged on. Then, he gave speeches – like the one in Anacostia which Tough details – arguing for a wide-ranging approach to poverty in America. Higher minimum wages and better union representation featured, but also specialised parenting, nutrition and early education programmes.

If the campaign was anything to go by, the prospect of returning to this seems weak. In the parks and multi-purpose arenas in which Obama delivered his campaign stump speech, the mention of poverty was noticeably scant for a candidate largely relying on GOTV among poor neighbourhoods. If it was name checked it was in a more conventionally liberal way, usually about the need for more teachers – rather than at the heart of his moral vision as once before; his words had lost their transformative edge. As some observed, at times it was like listening to a John Kerry speech.

Prior to that, in office, Obama put up none of the fight for an increase in the minimum wage that he had pledged. He gave not one single speech on poverty itself. Many of the programs he once envisioned exist but remain under-funded and minuscule compared to his initial vision. The basis of union organisation remains weak, as legislation aimed at strengthening it fizzled out early on.

Little of this is Obama's fault alone, of course, but it speaks to a nation's priorities. It's part of a wider cultural blind spot in the US. As Harrington wrote all those years ago, a key dimension of poverty in America is its invisibility to many people. There are certain neighbourhoods most folks don't go into, certain parts of town many go their whole lives without seeing, especially in places like Washington. There's little space in the 'American dream' narrative for those who don't pull themselves up to greatness, or the middle class, but who quietly struggle for their whole lives. It's time the President carved one.

As in the UK, the problem is one not just of unemployment but perilously low wages and economic insecurity. The percentage of those working but still in poverty is at its highest in nearly two decades; average wages are in a thirty year slump. And more and more Americans are falling closer to the threshold.

For this reason, it's particularly welcome that Obama prioritised, fought for and won protection of the Earned Income Tax Credit and Child Tax Credit in the recent fiscal cliff negotiations, which the Republicans had earmarked for abolition. Beyond that, though, he urgently needs to rediscover the spirit and ideas that animated his early words and interventions on poverty, like the one in Anacostia. African-American community leaders are gathering this week to pressure the President into making urban poverty a priority for his second term.

There's no doubt that Obama remains a deeply intelligent and thoughtful man, of authentic social compassion. But his record on poverty is a case study in his journey from transformational candidate to good, solid but unspectacular liberal incumbent. He is said to worry about his place in history in this respect, and has asked historians how he can match up to likes of Lincoln. Bringing poverty out from the political fringes offers him this opportunity. For the Democrats, too, it can no longer be dismissed as a 'core vote' concern which turns off swing voters – if they are to replicate 2012's voting coalition in 2016, turnout among minority voters is the swing vote. They will need to act and deliver on a malaise still ubiquitous in far too many of those voters' lives. An electoral imperative has been given to an issue which should long ago have been a moral one.