Remember Florida? The state whose "hanging chad" controversy left the outcome of the 2000 presidential race hanging in a balance for weeks, until the US supreme court finally intervened to hand the presidential election to George W Bush, even though Al Gore won more people's votes?

Well, the "sunshine state" is back at the centre of debate, thanks to a brewing conflict over whether its presidential primary – traditionally held well after the early contests in Iowa, new Hampshire and South Carolina – should be moved up to reflect the state's expanding population and growing electoral importance. Supporters of the move say the current primary system is archaic, because it skews each party's nominating battles in favour of small rural states with ethnically narrow demographics and ideological voting patterns, rather than more diverse, nationally representative populations like Florida's.

The debate's hardly new. In 2008, after wrangling with their national party leadership, Florida Democrats unilaterally moved their primary date up, leading the national party to strip the state of its delegates. Though perhaps not intended, that move helped tilt the Democratic campaign in Barack Obama's favour.

Republican party leaders threatened to do the same in their own Florida primary, but they ended up backing down, and John McCain, who won Florida, after winning New Hampshire and South Carolina, used that victory to drive Mitt Romney and New York city's former mayor, Rudy Giuliani, out of the race, effectively sealing his nomination. And Florida proved to be one of the most closely contested states in the general election, with Obama just narrowly edging McCain.

So far, none of the GOP presidential candidates has taken a position on the early primary issue, but two candidates, Jon Huntsman and Mitt Romney, are already looking to Florida as a major campaign springboard. Romney says he'll participate in only a handful of debates, but two will be in Florida. And Huntsman, in an even more telling sign, has just established his national headquarters in Orlando.

And, of course, the GOP convention itself will be held for the first time in Tampa, on the state's south-western coast, long considered a Democratic bastion. By 2016, in fact, it's likely that Florida will replace South Carolina as the GOP's traditional "bellwether" state, meaning that winning here could trump a candidate's showing in other contests, and foreshadow – as South Carolina does now – who'll become the party's nominee.

Of all the demographic changes pushing Florida to the forefront, none perhaps is more important than the state's rapidly diversifying Latino vote, which, at 20% of the state electorate, is large enough to decide its primary. Long considered reliably Republican, due to the dominance of its anticommunist Cuban American exile community, the Florida's Latino population now includes sizable numbers of Puerto Ricans and Central Americans, as well as Venezuelans and Colombians. Puerto Ricans, who've traditionally divided time between the island and the north-east, generally vote Democratic, and in Florida, their numbers have grown to the point where Cuban Americans are no longer the Latino majority.

The impact of the state's changing Latino demographics, including the growing diversity of its Cuban American community, was apparent in 2008, when, for the first time in history, a Democratic presidential candidate won a majority of the Latino vote in Florida. Obama's victory spread, 56% to 41%, was large enough to provide the margin of difference in his 50-49% victory over McCain.

The GOP, of course, wants Florida back – one of the reasons it decided to place its 2012 convention here. And thanks to the stalled economy, and public upset over "Obamacare", there was a shift last November. Tea Party favourite Marco Rubio, a Cuban American, won the open Senate seat, replacing moderate Cuban American Mel Martinez, while another Republican conservative, Rick Scott, captured the governorship. The state's legislature also went Republican, as many voters hurt by the recession, including independents drawn especially to the charismatic Rubio (who won an outright majority of the Latino vote), abandoned the Democrats.

Florida, in fact, is likely to become a major testing ground for conservatives who insist that their hard line on illegal immigration, which both Rubio and Scott endorse, will help not hurt them with Latinos. The state legislature, backed by Scott and, with some reservations, by Rubio, has already proposed some of the most draconian anti-immigration legislation in the country. But more moderate Republicans, led by former Governor Jeb Bush, a moderate, want to see his party embrace comprehensive immigration reform. Its failure to do so was one of the reasons that Bush, despite the powerful backing of the national GOP establishment, decided not to run for president this year.

But who knows? The pending entry into the GOP race of Texas Governor Rick Perry, and the recent surge by Representative Michele Bachmann, could well lead Jeb to reconsider, some analysts say. And there's also the huge problem posed by Scott's rapidly fading popularity – his abysmal 29% approval rating is the lowest of any sitting governor – which has deeply embarrassed Republicans not only in Florida, but nationally. It's already starting to turn what looked like a sure-bet win for the GOP into a "toss-up" again.

Move the primary up? If things continue this badly, Republicans might just want to suspend their contest altogether. And while they're at it – move their convention, too.