It's now midterm election season, and millions of voters are getting tons of emails, texts and phone calls they might not have even signed up for.
University at Buffalo professor and political communications expert Jacob Neiheisel says many political campaigns build and grow lists, and those often snowball over time and get passed down — or sold — from one campaign to another. Westcott, from the nonpartisan political data firm L2, says a lot of this information may feel individual and personal, but that campaigns are often using it as part of broader efforts to reach certain kinds of voters.
"If you wanted to run a broadcast TV ad and you had to advertise to everyone who was watching 'Friends' or the nightly news or whatever, but platforms like Facebook introduced really narrow targeting parameters where advertisers could target people based on their interest in dogs or or in pickup trucks," Edelson said.
But for all of this work to gather data and reach out, it’s worth noting this may only swing a small number of people, which could make a big difference.