A Jolt reader who works in the advertising industry weighs in on Rick Santorum’s 1,000-point television ad buy in South Carolina:

Buying at that level could either be a big deal or a very big deal. Here’s why: I’m assuming that 1,000 points means 1,000 Gross Rating Points [GRPs]. GRPs are an index. A 100 GRP buy means that everyone in the station or channel’s audience is exposed to your message an average of once; some people may see it twice, some once, some not at all. A decent television buy is of the order of 150-200 GRPs per week. So if they’re buying 1,000 GRPs over the two weeks between now and January 21, that’s 500 GRPs per week, or two-and-a-half times the normal buy’s weight. If the 1,000 GRPs are concentrated in one week, that’s five to 6.7 times the weight and frequency of a normally effective television buy.