As the Republican presidential race turns south, the key players to watch appear to be not the candidates emerging from Tuesday's New Hampshire primary but the super PACs who are supporting or opposing them.

In South Carolina, where the next votes will be cast in a Jan. 21 primary, local political observers and television executives tell Sunlight that the new political entities—most of which have yet to disclose any sources of their funding—are dominating the airwaves, far outspending the candidates. In Florida, which holds its primary on Jan. 31, a super PAC backing New Hampshire winner Mitt Romney just announced a $3.6 million ad buy.

This spending underscores the influence of these outside groups, whose importance may grow further since the FEC is considering a new request that would make it easier for corporate or union political action committees to accept unlimited money for independent expenditures, as super PACs can. 

MORE: See an up-to-date interactive table of the latest presidential super PAC spending here.

TV executives in Columbia, S.C., one of the state's major media markets, say the new super PAC spending represents an unusual windfall in a very short period of time compared to past elections. The super PAC supporting GOP candidate Newt Gingrich claims to be buying $3.4 million in TV time just as the pro-Romney Restore Our Future will be spending another $2.3 million on TV spots there. That will nearly double the amount spent on advertising in South Carolina so far—a total that the Associated Press over the weekend put at $3.1 million. 

“The big difference this year is how compressed the time period is,” said Rich O’Dell, general manager of WLTX in Columbia, a CBS affiliate. Scott Sanders, the general manager of WIS, Columbia’s NBC affiliate, agreed and added that super PACs are responsible for most of the spending this year.

“The PACs are definitely making an impact because the candidates aren’t spending as much as each individual candidate spent four years ago,” Sanders said.

Under the law, the candidates and super PACs are not supposed to coordinate how they spend their money. But earlier this week, Gingrich tacitly acknowledged how intertwined the super PACs have become with the candidate’s strategies as he discussed Winning Our Future's new ads on MSNBC’s Morning Joe. “Let’s be honest about a competitive business,” he said.

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His defense of the group's decision to go negative on Romney made it sound as if he had been a part of it. “So you either decide to leave the field or you decide you will engage in what you have to in order to match someone who just spent three and a half million dollars attacking you,” Gingrich said.

Gingrich also seemed to know details about the sources for a 27-minute documentary that Winning Our Future intends to distribute about Romney's work at the private equity firm Bain Capital. Excerpts, which portrays Romney as profiteering at the expense of employees of the companies his firm took over, are scheduled to begin airing today in South Carolina.

Gingrich has sharply criticized Romney for his connections to the outside group supporting him. Both committees are run by the candidates’ former staffers.

Overall, spending on political ads is not necessarily higher than it was in South Carolina four years ago, local TV executives said. Sanders estimated that it is just 70 percent of the 2008 total. There are two big factors behind the dropoff: both parties had competitive races in 2008 and spending started much earlier. O'Dell said some ads began as early as September 2007. This time around, the pro-Perry super PAC Make Us Great Again launched a South Carolina ad campaign in November, but the major influx of super PAC money has just arrived this week.

A super PAC supporting Rick Santorum—called Red, White & Blue—also bought ad time in South Carolina recently, ponying up about $200,000 on Saturday.

Another factor driving this bonanza is the state’s cheap ad market. “South Carolina media markets are very cheap as far as buying ads so you get a lot more bang for your buck than you would in Florida,” said Scott Buchanan, as associate professor of political science at The Citadel, a college in Charleston, S.C. 

Restore Our Future’s new ad buy would, initially, use a positive spot that originally aired on Dec. 27 promoting Romney’s record as a businessman and former head of the International Olympic Committee, according to the New York Times.

Super PACs were not around in 2008. Made possible by two federal court decisions in 2010, these groups can collect and spend unlimited amounts of money from corporations, unions and individuals.

In Iowa, Gingrich criticized Romney for not disavowing the super PAC’s ads in Iowa, which he amounted to a "smear campaign." "Understand, these are his people running his ads, doing his dirty work while he pretends to be above it," Gingrich said at the time. After Restore Our Future spent millions on ads criticizing Gingrich in Iowa, the former House speaker's poll numbers plummeted. After having challenged Romney for the lead, he finished in fourth place in the Jan. 3 caucuses.