A cool data story I heard on the radio lately was about what neighborhoods in New York City gave the most money to each candidate. The source is this Gothamist piece that visualizes the data underlying the story: https://gothamist.com/news/2020-money-race-chelsea-boosts-buttigieg-biden-takes-ues.
It sparked my interest because while New York is not a battleground state in the primary, this reporting illuminates the financial influence it can have on an election (which is just as important if not more so in the competition to be the candidate). It's illuminating and telling of New York's culture which neighborhoods rallied behind which candidate, and the numbers themselves are revealing about how much momentum each candidate has.
The reporter was then able to use that data to interview people and get their reactions to why a certain candidate was popular in their neighborhoods, further contextualizing the piece and providing a local hook to a national story.