US Elections 2020: Defining 'Swing States'

Swing States, also sometimes called 'Toss-Up states', are at the epicenter of many prediction models and the target of millions of polling dollars because of the unpredictability of the votes that these states can swing to transform a candidate into the next occupant of the Oval Office. But what makes a swing state a swing state? All it means is that the campaign is closely contested and either the Democratic or Republican presidential candidate could reasonably win. 

The data tells an interesting story about swing states, because no state was among the swing states in all four of the last presidential elections. Only three states—Florida, North Carolina, and Ohio—were swing states in three of the four last elections. It should come as no surprise then that the predictive quality around swing states and outcome elections is so weak, as FiveThirtyEight's analysis shows.