(CNN) During an event on school prayer on Thursday in the Oval Office, CNN's Betsy Klein spotted something interesting out on President Donald Trump's desk. It was a map.

Spotted on the resolute desk in the Oval Office during the President's event on school prayer: a map of 2016 election results by county pic.twitter.com/28mgWtGSyz — Betsy Klein (@betsy_klein) January 16, 2020

A county-by-county map of the 2016 election results, to be exact. (The 2016 election was 1,165 days ago. But who's counting!) It's a map that Trump -- as well as his son Donald Trump Jr. -- regularly turn to as a way to suggest his dominance in the last election. In October 2019, for example, Trump tweeted the county-by-county map -- incorrectly , it turns out! -- with the words "Try to impeach this" written over it.

You can see why Trump likes the map so much. There's loads of red (signifying counties that voted for him) and a relatively small amount of blue (counties Hillary Clinton won) on it. Visually, it makes it looks like Trump won a red wave election in 2016.

Which, from a county perspective, he did! Trump won 2,626 counties to Clinton's 487 in the last presidential election, according to the Associated Press

But that data point -- and the county-by-county map it powers -- is deeply deceiving. Why? A very simple reason: Land doesn't vote, people do.

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