The Seattle Seahawks and the Denver Broncos aren't the only entities who have a lot at stake when Super Bowl XLVIII debuts on Fox this Sunday (weather permitting).

With 30-second spots in the game going for around $4 million a pop, a lot of different media properties and sponsors are under extreme pressure to perform. Fox will want to do all it can to keep viewers tuned past halftime while taking advantage of the massive audience to hype everything from new programs to other ventures from its parent company, 21st Century Fox. Marketers will be under the gun to prove the millions they plunked down to appear in the game do more than generate retweets, Facebook likes and YouTube views. Social-media chatter is fun to note, but there's little direct correlation between trending on Twitter and notching a revenue windfall for the first quarter.

Who's feeling the heat? Variety looks at a range of players who will likely have sweat on the brow no matter how cold it may be in MetLife Stadium this Sunday:

Fox: The broadcaster's ratings performance will help advertisers determine if Super Bowl viewership has room to grow or has hit a plateau.

For the last several years, the Super Bowl audience was on the upswing, first surpassing the record for the most-watched program of all time (CBS's 1983 telecast of the "M*A*S*H" finale) in 2010, when it notched a viewership of about 106.5 million, and then growing more still.

Until last year, that is. That's when a CBS broadcast of Super Bowl XLVII was marred by a 34-minute power outage. In 2013, an estimated 108.4 million people watched the CBS telecast, down from 111.3 million who tuned in to NBC a year earlier. A rise in viewership will give advertisers confidence the gridiron classic's hefty price tag is worth it as big TV audiences continue to splinter. A dip could make things a little tougher for NBC, which will broadcast the event in 2015.

Pepsi: The popular soda maker will test the value of the Super Bowl halftime show by cutting the commercials it has run throughout the game.

For more than two decades (give or take a year), the Super Bowl has been filled with multiple spots from Pepsi. Whether it's a competitive poke at rival Coke, or a visit with Michael J. Fox or Justin Timberlake, Pepsi has been an integral member of the game's ad roster.

In 2014, however, the beverage maker will forgo a lot of the hoopla and focus its efforts on the halftime show, which it is sponsoring for the second time in a row. Will a single 30-second spot and a few songs by Bruno Mars and the Red Hot Chili Peppers carry the day when a bunch of funny and celebrity-laden ads once did the same? The Super Bowl's other ad pillar, Anheuser-Busch InBev, will no doubt be watching the results.

Big Yogurt: At a time when people are snarfing down buffalo wings, nachos and soda, can this good-for-you option get people to change their habits?

Typically a place for soda showdowns, and snack-ad attacks, the Super Bowl this year will be the site of a yogurt war. Greek-yogurt upstart Chobani will throw down with Dannon's Oikos, returning to the Super Bowl ad roster after taking a year off (it debuted in 2012). Chobani will send a healthy-snack craving bear up against a Dannon-backed reunification of the cast of the old ABC series "Full House."

"New Girl" and "Brooklyn Nine-Nine": If these two shows, set to air after the post-game show, can't convert part of the Super Bowl crowd into regular watchers after "Girl's"continued buzz and "Brooklyn's'" surprise Golden Globe, there may not be much more Fox can do.

There's no guarantee a Super Bowl can transform a budding series into a hit or transform a critically acclaimed program into a blockbuster. Among the well-liked programs that have gotten a Super Bowl berth: ABC's "Alias" and CBS' "Undercover Boss." The game has also served as launching pad for ABC's "The Wonder Years" and NBC's "Homicide:Life on the Street."

Stephen Colbert: The faux-outraged host of Comedy Central's "Colbert Report" regularly flogs products on his show, but does he have the stuff that pitchmen are made of?

Super Bowl XLVIII may well serve as a test. Yes, celebrities have always used the occasion, but more often than not, they are decidedly C-list: South Korean rapper Psy for Wonderful Pistachios or Kim Kardashian for Skechers. In recent years, that has begun to change. Did Clint Eastwood's patriotic appearance on behalf of Chrysler in 2012 spur new thoughts about top-flight stars making a run in commercials?

In 2014, Scarlett Johansson will hold forth for SodaStream while Arnold Schwarzenegger and Don Cheadle will add forth to the usual commercial suds for Anheuser-Busch InBev.