AMONG the shelves in Libreri Mapou, a bookshop in a row of pastel-fronted stores in Little Haiti, is a dull-looking door. Beyond it, up a staircase, lies a technicolour trove of paintings, statues, embroidery, memorabilia of bygone political campaigns and honours awarded to the proprietor, Jan Mapou. Imprisoned under Papa Doc Duvalier, Mr Mapou fled, moving to Miami in 1984 and establishing himself as a radio host, Creole-language advocate and poet. For years activists, lawyers and artists gathered above his shop.

They still do, though much of the action has moved around the corner to the swish Little Haiti Cultural Centre. A candidate in Haiti’s disputed presidential race recently spoke in its classy theatre (many locals cannot vote in their ancestral homeland, but their remittances, estimated by the World Bank at $1.1 billion in 2012, give them a say); one of the centre’s galleries currently displays photos of Little Haiti by youngsters from Little Havana, and vice versa. In his adjacent studio Edouard Duval-Carrié, a Haitian-born artist, creates haunting nocturnal beach scenes, etched in glitter—a skeleton in a voodoo suit, a gunboat on the horizon—intended, he says, to illuminate the darkness behind rich-world fantasies of the tropics.

The short stroll from Libreri Mapou to the cultural centre maps the evolving contours of the Haitian-American community. Built by the city government and opened in 2009, the centre is a testament to the community’s growing influence; the resilient links to Haiti exemplify the hybrid identities many immigrants now maintain. In a twist characteristic of this postmodern era of powerful diasporas and hotly contested microconstituencies, these features—Haitian-Americans’ progress, and their long memories—might play a role in November’s presidential election.

The Port-au-Prince primary

Counting immigrants and their descendants, there are officially around 1m Haitian-Americans, a population swollen by successive political and natural calamities (the true figure is doubtless higher). Almost half live in Florida, especially in and around Miami; in some counties they represent the biggest minority group. An early, small wave escaped Duvalier’s regime in the 1960s, largely for New York; a bigger, poorer, more rural one arrived, mostly in Florida and by boat rather than plane, in the 1980s. Less educated, slower to assimilate, they were also stigmatised by a supposed association with AIDS.

In Miami’s bubbling ethnic stew, the tensions of those years have only partly dissipated. Among Haitian-Americans, as others, resentment lingers over Cubans’ preferential immigration status. As Mr Mapou puts it, Haitians had the extra misfortune to be victimised by a right-wing dictator, and so instead of the “red-carpet treatment” were liable to detention and repatriation. There has been friction with black Americans over jobs and local politics—though younger Haitians are much readier than their elders to see themselves as African-American, too. “When my son walks down the street, he is black,” says Sandy Dorsainvil, the cultural centre’s director. “Colour shows first.”

Beneath that convergence, though, histories are different—which gives hope to Michael Barnett, chairman of Palm Beach County’s Republicans. In the past, he says, Haitian-American votes have been taken for granted by the Democrats and “written off by Republicans”. But Haitians are not instinctively suspicious of his party as other black Floridians are. Many are socially conservative; rising numbers are well-off. Mr Barnett points, as a model, to the 2014 campaign of Rick Scott, Florida’s governor, who visited Haitian evangelical churches and ran radio adverts in Creole.

But perhaps the main ground for Republican optimism involves events in Haiti itself—in particular, allegations of mismanagement in the relief effort following the earthquake of 2010. Various agencies are implicated, but, overwhelmingly, one surname: Clinton. Bill was a UN envoy, Hillary secretary of state. As well as botching the aid, she is widely thought to have strong-armed Michel Martelly, the unloved former leader, into office. Some still grumble about Bill Clinton’s ruinous insistence, as president, that Haiti drop its rice tariffs. He cannot have anticipated that this arcane bit of trade policy might one day interfere with his wife’s presidential bid.

Even if these gripes merely keep some would-be Democrats at home, they might matter. Florida’s result was the country’s closest in the election of 2012. In 2000, of course, Al Gore lost it, and the presidency, by 537 votes. “If 537 Haitians decide not to go to the polls,” the outcome could change, says Jean Monestime, a Democrat who came by boat as a teenaged refugee, with no English, and is now chairman of the Miami-Dade county commission. Jean-Philippe Austin, an oncologist and Democratic fundraiser, says he has advised the Clintons that Haitian-American votes “aren’t going to be automatic.” Mrs Clinton needs to explain the relief effort, he says.

Still, some countervailing factors endure. Immigration policy remains a leading concern; should he be the Republican nominee, Donald Trump’s xenophobia is unlikely to go down well. Overall Florida’s Haitian-Americans are still poorer than average and more likely to be jobless. Gepsie Métellus of the Sant La Haitian Neighbourhood Centre, which offers employment and health-care services, frets that some Haitian teenagers are emulating the “bad boy” personas of their renegade peers.

Yet, as is common in modern cities, even as Haitian-Americans struggle with hardship they also face the deracinating effects of prosperity. “Gentrification is in full force now,” says Father Reginald Jean-Mary of Notre Dame D’Haiti Catholic congregation. “It is Little Haiti in name only.” As Miami’s downtown and smart brands encroach on the old neighbourhood, rising rents are pushing people out, even as others leave voluntarily for more space and better schools. They trek back for Notre Dame’s child-care programmes and Creole services in the beautiful new church: one stained-glass window depicts Christ welcoming a boatload of refugees, Miami’s skyline looming behind them. Meanwhile, in an area recently considered dicey, tourists now come to browse Haitian crafts. “It doesn’t get any more American than that,” reckons Ms Dorsainvil.