'There are two types of power," said Linda Jeffers, addressing an accountability session of New Orleans mayoral candidates at the city's Trinity Episcopal church. "Organised money and organised people." Since Hurricane Katrina, the battle between those two forces has shaped the struggle to rebuild New Orleans. With mayoral elections on Saturday it is set to intensify.

The one thing both sides seem to agree on is that neither wants the city to return to the way it was before the hurricane. The people of New Orleans, most of whom are black and many of whom are poor, want schools that will educate their children, jobs that will pay a living wage, and neighbourhoods where capital investment matches the large pools of social capital created by their churches and close-knit communities. Organised money has something else in mind: the destruction of many of those communities and permanent removal of those who lived in them, a city that follows the gentrification patterns of racial removal and class cleansing that have played out elsewhere in the US.

Under these circumstances, the organisation of people has been impressive. Grassroots groups have done a remarkable job of gathering those scattered throughout the country into a political constituency. Jeffers spoke to an audience of more than 500 people who had been bussed in from Tennessee and elsewhere in Louisiana, as well as over 1,000 who watched the session on satellite in Austin, Dallas, Houston and San Antonio. Five days later Jeffers, a leader with the Industrial Areas Foundation (IAF) who moved from New Orleans to Houston after Katrina, schlepped through the unforgiving Houston heat distributing food and signing up evacuees for their absentee ballots. Meanwhile organisations have been ferrying people from neighbouring states to satellite polling stations dotted around Louisiana for early voting.
But the circumstances have been dire. Evacuees in Houston exist in a constant state of bureaucratic harassment. Last week the Federal Emergency Management Agency (Fema) in effect issued 25,000 eviction notices to evacuees in Houston. Almost half have no health insurance because they lost their jobs in the storm; more than one in eight children have been going without prescribed medication. Contrary to Barbara Bush's infamous predictions, this is not working out very well for them.

In this context, the New Orleans mayoral elections have particular significance. Whoever wins will have the task of mediating between organised people and organised money, and therefore shaping the priorities for rebuilding the city. But by almost any standard these elections are neither free nor fair. Fewer than half the city's residents have returned. Yet requests for polling stations to be set up in the major towns outside the state where many have resettled were rejected by the federal courts. "You're telling me they can do it in Iraq but they can't do it here?" said Walter Milton, a leader with the IAF.

As a result, people have to either travel hundreds of miles to vote or organise a postal vote. The overwhelming majority of those most adversely affected are once again black and poor. So Jim Crow is on the ballot. But this is the New South with a new, more subtle, but no less effective, racism. Black demands for full citizenship no longer fall foul of the law of the land but instead the law of probabilities. They were more likely to be flooded, more likely to be displaced, the least likely to be able to return, and therefore the least likely to be able to vote.

With organised people thus thwarted, organised money has asserted itself with great effect. The current mayor, Ray Nagin, was the candidate of big business. He came to power in 2002 with a minority of black support and the overwhelming backing of whites and the business community. But he rejected a plan by the Urban Land Institute in November. The institute presented a map with three "investment zones". The areas earmarked for mass buyouts and future green zones, and the last to be invested in, were overwhelmingly populated by African-Americans and the poor. New Orleans needed a smaller footprint, it said; but it would be big enough to kick out African-Americans and the poor.

When Nagin balked at the plan, business looked for a new standard-bearer. Its favoured son this time is Ron Forman, head of the Audubon Nature Institute. But as a backup, business interests are also investing in the local political aristocracy in the guise of Mitch Landrieu. Landrieu, Louisiana's lieutenant governor, is the brother of Mary Landrieu, a Louisiana senator, and the son of Moon Landrieu, New Orleans's last white mayor, who left office in 1978. So the people have a vote, but business has picked both the incumbent and the two main challengers.

Unlike Nagin, both Landrieu and Forman are white. With little to choose between the three on substantive issues, the decision may come down to the symbolism of race. Given everything that happened and continues to happen after Katrina, this is probably inevitable: given the needs of the city, it is regrettable. It will take more than melanin to rebuild the city; indeed it is an obsession with melanin that continues to destroy it.

Only this time, no one is watching. Like teenagers discovering sex, the American media developed an intense fascination with the mundane facts of American life following the hurricane: namely, the glaring disparities in race and class that persist and pervade. Having gorged themselves on the undeniable evidence of glaring disparities in race and class, they soon got sick and went to sleep.

Up in the mostly white and wealthy Garden District, the Boulangerie on Magazine Street offers a delicious choice of croissants. Down in the ninth ward they are still finding dead bodies - nine in March, some half-eaten by animals, plus a skull.

But there is no dramatic backdrop to the systematic and systemic exclusions of African-Americans this time around. It's as though corpses have to be floating down the street and thousands stranded without food or water before racism is once more worthy of note here. "I came down off my rooftop and I walked through the waters," said Jeffers. "And now I feel like they're taking me back on to the rooftop." The organised people of New Orleans keep trying to move to higher ground: the organised money keeps trying to sell the land from under their feet.

g.younge@guardian.co.uk