Lee Atwater had a rule of thumb about campaigns and public opinion: The truth is whatever people believe it is. Atwater—Ronald Reagan and George H.W. Bush’s sharp-elbowed evangelist for the power of paid media—wanted that to be true back when he was buying radio spots and bombarding voters with direct mail. But the adage feels even more profound today, in a world defined by algorithms, identity politics, and the choose-your-own-adventure maze of partisan media.

To wit: A new poll this week from Puck and Echelon Insights confirms that a lot of voters right now are simply choosing to believe what they want to believe—on issues like crime, the economy, and the legal perils facing Donald Trump. Maybe these voters are underinformed, maybe they have partisan blinders on, or maybe they’re tuned out and are just telling pollsters what they think they want to hear. Whatever the case, a string of recent polls reveals a frustrating gap between perception and reality. It’s a big reason Joe Biden could lose in November.