STEVE INSKEEP, HOST:
Some of the most important real estate in presidential politics is right in front of your face. It's the screen on which millions of voters look at Facebook. That social network has become a key place for campaigns to advertise, as NPR's Scott Detrow reports.
SCOTT DETROW, BYLINE: Every presidential campaign has to be on Facebook. For Ben Carson, Facebook kind of is the campaign.
KEN DAWSON: That is our hub of communication. And we really see it as the heart of our campaign.
DETROW: Ken Dawson is Carson's chief marketing officer. He's in charge of digital strategy. Sure, Carson is out there in Iowa and other key primary states. But on Facebook, he has more than 4 million followers. That's more than any other presidential candidate. Carson's Facebook feed is a constant stream of posts and videos.
(SOUNDBITE OF POLITICAL AD)
BEN CARSON: Of, for and by the people - we need a government that actually understands that.
DETROW: In addition to that, the campaign is running a whole lot of advertisements on Facebook.
DAWSON: Welcome to the operating room (laughter) pun intended.
DETROW: Dawson brings me into Carson's headquarters, a small set of rooms on the first floor of a northern Virginia office building. About a dozen people sit in front of computers. Like a hospital, the walls are a dark lime green. Dawson opens up his laptop to show me the page cracking all 240 ads the campaign is currently running on Facebook. Nearly every single one is targeted to a different set of people. The campaign can send its ads to specific groups of people by loading in lists of supporters and matching them to Facebook accounts. Often, Dawson says these are the names and email addresses of people who have shown up at a rally, given money or signed up on the campaign website.
DAWSON: We can import those audiences. We can focus on them and make sure that they're hearing our messages. We can target them around how many ads we want to serve them, how often we want to serve them and then build calls to action around each one of those ads.
DETROW: And knowing these people are already strong Carson supporters, those calls to action can be much more specific than a typical TV ad. They can urge people to volunteer or give money. Facebook can also take those lists and create a new audience of similar people for campaigns to target. Erik Hawkins runs Facebook's political sales, among other things.
ERIK HAWKINS: So we can help you build audiences that look just like the custom audiences you have. So if you have a custom audience of, let's say, your most active donors, maybe you want to talk to a lot of people who are very similar to them. And we can enable you to do that.
DETROW: Hawkins points out these look-alike lists are only done in large anonymous groups. Facebook isn't telling campaigns the names of specific people who are similar to their supporters. Campaigns can also target ads based on the information people share in their profiles. Strategist Ken Dawson says the Carson campaign sends ads to people based on location, age, gender or what you like.
DAWSON: If we're talking about religious liberties, we would start with very conservatives. But then maybe get down to even occupation - people who are pastors or work within a church or affiliated with Bible groups.
DETROW: It's a good formula, but it doesn't always work.
JOSH WILSON: It's definitely an experience I've had in the past, where you can just kind of feel yourself being targeted, and you just kind of roll your eyes.
DETROW: Josh Wilson is a pastor and does post on Facebook about Bible study. But he says he's more of a political agnostic. He gets fed up with the conservative ads in his newsfeed.
WILSON: Working for a church, you definitely kind of get lumped in with what would be the stereotype churchy person that - well, if you're interested in that Bible study, you're probably also interested in this conservative candidate.
DETROW: But by and large, these tools do let campaigns talk to the exact sort of people they're trying to reach at any particular time. So as the election approaches, expect to see just as many ads in your newsfeed as you do on your TV. Scott Detrow, NPR News.