Not even the Weather Channel is safe anymore. Thanks to the explosion of money in politics and the imperative of reaching key voting blocs, political strategists are increasingly turning to cable television to spread a candidate’s message.

But buying the right package is still an art, and the delicate balance between cable and broadcast television advertising can mean the difference between a message penetrating an audience and an expensive one lost in the shuffle.

New campaign finance rules that have paved the way for millions of additional political advertising dollars have ensured that presidential campaigns and their associated Super PACs can purchase so much advertising time that, in some instances, a state’s entire inventory may be snapped up. This primary season, that has led campaigns to an increasing reliance on cable advertisements, which have come across a broader spectrum of channels than ever before.

Through the year’s first three Republican nominating contests—Iowa, New Hampshire and South Carolina— presidential candidates and the Super PACs backing them spent $32 million on television advertising. While the bulk of that advertising—a little under $30 million—came on broadcast television, the candidates also spent more than $2.25 million to run more than 68,000 individual ads on cable television, according to data from Republican ad buyers and NCC Media, a firm that represents cable companies and helps candidates place ads.

“Unlike a few cycles ago, cable is now seen as a viable tool to be used,” says Brian Walsh, president of the American Action Network, a Super PAC that backs Republican candidates.

Cable has asserted itself over broadcast as a significant presence in the daily lives of Americans. A decade ago, just four out of 10 minutes of television viewing happened on cable stations. Today, that number is closer to six in 10. And 90 percent of Americans pay for some form of television. The way cable systems are set up means advertisers can drill down below a standard broadcast media market to more accurately target the right voters.

“We can align our voter data or other metrics to determine what systems hold the concentration of what voters in certain areas,” says Tim Kay, NCC Media’s political director. “If elections are won by a few thousand votes, identifying them and targeting them becomes more important.”

During the Republican presidential contest, three different cable strategies have emerged: The Fox-only strategy put an enormous emphasis on Fox News Channel’s depth of reach among Republican primary voters. The broad-based strategy has tried to expand the electorate by targeting new voters who don’t otherwise watch Fox News. And the surgical-strike approach took advantage of key moments during the campaign to reach a broader audience and get more bang for a candidate’s buck.

Given the nature of the Republican electorate this year, it comes as no surprise that Fox News Channel has been the biggest recipient of cable ad dollars. About half of all cable advertisements in Iowa aired on Fox News, while 10 other networks aired 45 percent of the remaining spots. Almost every candidate aired advertisements on Fox, beginning in early July when Rep. Michele Bachmann began running small ad flights on the network’s channels in Cedar Rapids, Davenport, Des Moines, and Sioux City. Mitt Romney’s campaign ran cable advertising almost exclusively on Fox News in Iowa, to the tune of $151,000.