IN 1984 Ronald Reagan’s campaign aired a syrupy ad declaring: “It’s Morning Again in America”. It was designed to appeal to as many people as possible, showing pictures of Americans doing utterly mainstream things like going to work, getting married and loving their families. Ken Goldstein of the University of San Francisco calls this the “shotgun approach”.

Modern political ads typically use a sniper’s-rifle-with-telescopic-sights approach. Instead of selling a story for all Americans, they aim at specific groups, such as lovers of guns or abortion rights. Often, they warn members of these groups that the other party despises them and wishes them harm.

Consider the National Rifle Association (NRA)’s campaign against candidates who are insufficiently pro-gun. Its televised spots link such candidates with Michael Bloomberg, a former mayor of New York who bankrolls a national anti-gun campaign. A voiceover says: “In an elegant New York City mansion, billionaire Mike Bloomberg sleeps safely. A team of armed guards protects him. But Bloomberg wants to take away your right to self-defence...And [insert name of Democratic candidate] will help him do it.” The ad never spells out what Mr Bloomberg’s “extreme gun-control agenda” involves, so viewers can imagine that their local candidate wants to grab their hunting rifles. (This is unlikely, but several want to stop gun sales to criminals and the mentally ill.)

What the campaign lacks in policy specifics, it makes up for with cultural innuendo. It assumes that the viewer is poorer than Mr Bloomberg (a safe bet), more rural and suspicious of bossy New Yorkers. Another spot (pictured) quotes a disparaging remark Mr Bloomberg once made about a remote part of Colorado having no roads, and concludes that “Nobody insults your life like this guy.”

Targeted advertisements only work if you show them to the right people. That grew easier when Nielsen, a TV ratings firm, started including political questions in its surveys in the early 2000s, so strategists could find out which programmes the voters they were trying to reach were most likely to watch. Now, cable-TV firms sell campaigns data about subscribers’ individual viewing habits. It arrives anonymised, but with addresses, which can then be matched to the addresses on voter-registration and canvassing databases.

So if, for example, people living at addresses marked as potentially Republican happen to watch lots of golf, then a Republican candidate might buy ads on the Golf Channel. Indeed, according to a study by Echelon Insights, a political consultancy, 93% of political spots on that channel are Republican; on Comedy Central, by contrast, the ads are 86% Democratic.

By 2016 advertising will be even more precise, reckons Mr Goldstein. The newest thing offered by cable and satellite TV companies is called “addressable advertising”. This allows advertisers to buy the viewers they want rather than slots on particular programmes. So whatever the target voter watches, a campaign advertisement will appear in the middle of that show, via the set-top box. In January, Dish Network and DirecTV, two satellite firms, announced that they can reach some 20m households with directly addressable advertising. By the end of this year it may be possible to reach 50m households this way.

For campaigns, such targeting is thrilling: it means that money can be stretched further and potential swing voters really bombarded with ads. For outside groups, who mostly run attack ads, addressability is particularly helpful, because it allows several messages to be sent at once. For example, instead of running one ad, a campaign can air ads attacking Obamacare on one channel, gun control on another, and threats to Medicare on a third.

The worry is that technology may be moving too fast, says Jim Duffy of Putnam Partners, a Democratic-leaning political-advertising agency. Even as cable and satellite firms roll out new technology, more voters—especially younger ones—are switching to internet services such as Netflix or Hulu. These often feature no ads at all, or offer the option to skip them. Meanwhile, the sheer variety of content means that buying ads is even harder than on cable television.

A more immediate problem, however, is that when you aim all your firepower at narrow, clearly-defined groups, you may find you aren’t reaching enough people. To win an election you usually need to win over half of the electorate. Sometimes, that may require getting out the shotgun.