Dark Money Political Groups Target Voters Based on Their Internet Habits

… Online advertising companies have amassed vast quantities of information on what individual people read, watch, and do on the Internet. … These anonymous profiles of information are used to customize advertisements—like sending casino ads to someone who just bought a plane ticket to Vegas.

But these profiles are also increasingly used by political groups, which can decide which people to target with a message—and which people to avoid—based on the kinds of articles they read and the kinds of sites they visit. [cont.]

Lois Beckett, ProPublica