(CNN) The story of the 2016 election has often been told like this: "Donald Trump secured victory by breaking through the big blue wall in Michigan, Pennsylvania and Wisconsin." It's how you end up with all those stories about Trump voters in Midwest diners. Heading into 2020, there's still a lot of focus on those pivotal states.

But when you look at the electoral math, it's pretty clear that former Vice President Joe Biden would be wise to look beyond those states and make a heavy investment in Florida.

Florida was a very close state in 2016 . Trump won it by just 1.2 points, which is not significantly wider than the margins he won Michigan (0.2 points), Pennsylvania (0.7 points) and Wisconsin (0.8 points). The next closest state (Arizona) featured a significantly larger Trump win (3.5 points). In fact, the presidential margin in Florida has been within 6 points in every election since 1992, including when Democrat Barack Obama won it in 2008 and 2012. No other state has been within that range for so long.

The polling in 2020 makes Florida look like it will be close again. Biden holds a three-point advantage in the Sunshine State in an average of nonpartisan probability polls that controls for pollster. That's closer than Wisconsin (one-point Biden lead), and the same as what we see as in Pennsylvania. Biden is up four points in Arizona and five points in Michigan. (North Carolina, another close Trump won state in 2016, gives Biden a one-point edge, but the high quality polling there has been limited.)

Without knowing anything else, Florida would seem like a good investment for Biden. If the polling is to be believed, it's at least as good as Pennsylvania and Wisconsin.

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