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The Trump campaign has repeatedly credited its online prowess, particularly on Facebook, as a key to its 2016 victory.

Now, the Facebook employee who embedded with the Trump campaign to help it master message testing and iteration is working for Democrats. And he has revived one of the most important tactics he used for the Trump campaign at Acronym, a progressive nonprofit.

We wrote about the efforts of James Barnes and the Barometer team at Acronym on Tuesday, how they test the impact of their Facebook ads in real time through a series of surveys served to a custom audience before and after each ad campaign.

In tonight’s newsletter, where we embrace all things digital, we’re going to get a little more granular on three tests that Mr. Barnes and his team ran.