Pinellas county in Florida, along the Gulf Coast to the west of Tampa, is a particularly accurate political bellwether: it has reliably picked the winner of each presidential election since 1980, with the exception of George W Bush in 2000, writes James Politi.
Four years ago, Donald Trump won it by a little more than 1 percentage point. With Florida exceedingly close this year, Joe Biden will probably have to show solid gains in Pinellas, rather than just narrowly flip it, to prevail in the rest of the state.
According to the latest Realclearpolitics.com polling average, Florida remains very much up for grabs, with Mr Biden leading by just 0.9 percentage points.
On the eve of the election, former president Barack Obama speaks at a rally, campaigning for Joe Biden in Miami, Florida
There have been some signs that voter dissatisfaction with the economy is combining with Mr Biden’s nationwide gains among seniors, women, and the young to give the Democrat an edge in Pinellas.
Mr Trump’s most valuable weapon on the road to clinching a second term — his economic stewardship — has been blunted by the downturn that gripped America this year, pushing the overall US jobless rate up to the highest level for any incumbent president seeking re-election since the second world war.
In Florida the political fight over the economy has been particularly raw because the state is heavily dependent on services such as leisure, tourism and hospitality, which were hit by the early lockdowns and the second peak of infections in the summer.