GROVERS MILL, N.J. - As he stood along Quaker Bridge Road Thursday morning, gripping a stop sign like a football yardage-marker, an orange-vested highway worker wearing a blue-knit New York Giants cap chatted with a co-worker in a green Eagles hat.

Welcome to New Jersey's demilitarized zone, a no-fan's land between the hostile North-South empires of Giants and Eagles supporters, a place where geography, history and the media have combined to create a civic schizophrenia – particularly when it comes to sports loyalties.

This week, 71 years after Orson Welles' located his notorious radio version of "The War of the Worlds" here, this little town southeast of Princeton again was at the center of an historic conflict, this one featuring helmeted earthlings instead of ray-gun-wielding Martians.

"Everyone around here is excited about the game," resident Tom Carmichael said of today's NFC divisional playoff contest between the Eagles and Giants. "But if you're trying to figure out whether more people will root for the Giants or Eagles, don't even bother. I can almost guarantee you it will split almost exactly down the middle."

Ben Franklin once noted that New Jersey was a state "tapped at both ends" by the powerful metropolises. The gravitational pulls of Philadelphia and New York weaken somewhere near here, producing a vortex of mixed allegiances.

As Philadelphians travel north on I-95 or the New Jersey Turnpike en route to today's game at the Meadowlands, they'll be passing through the heart of where the cultural, economic and sports spheres of New York and Philadelphia converge.

No one is exactly sure where North and South Jersey, or Giants country and Eagles country, begin and end. Some say it's the Garden State Parkway's Driscoll Bridge in Middlesex County. Other suggest it's the Raritan River, or the place where the 201 and 609 area codes used to converge.

Most will agree, however, that this land of the Giants Eagles runs diagonally across the belly of the state, from Phillipsburg in the west to Toms River in the east, and from Princeton in the north to Trenton in the south.

Here, it's not just fans of the two NFC East rivals who coexist in the same neighborhoods, often on the same streets, but Wawa and 7-Eleven customers, Inquirer and New York Times subscribers, hoagie and hero devotees.

"For example, there's a Dunkin' Donuts on Route 33 just above Trenton where they sell Eagles cups and Eagles memorabilia," said Steve Chenoski, a Mercer County native who recently completed a film, New Jersey: The Movie, exploring the divide between the state's North and South. "And five minutes away, there's another one that has all Giants stuff."

Unlike in the state's northern and southern counties, there's an ebb and flow to the spheres of influence all along the sports divide.

The early 21st-century housing boom, for example, sent thousands of New Yorkers and North Jerseyans into the areas surrounding Phillipsburg, places that traditionally had leaned toward the Eagles.

When the Easton, Pa., newspaper, just across the state line, asked readers before the most recent Super Bowl appearances of the Giants and Eagles to write in their reactions, Giants responses outnumbered those for the Eagles by 3-1.

The Eagles, meanwhile, hope that by training in the Lehigh Valley, they've countered some of the Giants' incursion into what had been their territory.

The teams recognize the potential for growth in Central Jersey and are attempting to expand their geographic clout.

"I really think teams in both cities are using minor-league teams to expand their geographic bases," Chenoski noted. "The Yankees and Devils had farm teams in Trenton. And the Phillies stuck a team in Lakewood, which had always been New York territory."

A 31-year-old middle-school teacher who now resides in Hoboken, Chenoski said his documentary, which he has submitted to film festivals in both regions, attempted to locate the precise dividing line.

He won't reveal its conclusion, but admitted it closely paralleled the old Keith Line, which was drawn in the 17th century to distinguish East Jersey from West Jersey.

Chenoski's mixed sports loyalties are typical for the area where he grew up. He likes the Eagles and Phillies, but prefers the New Jersey Devils to either the Flyers or Rangers.

"But if the Giants ever changed their names to the New Jersey Giants, I'd have to reconsider my Eagles loyalty," he said. "And I think a lot of people [in that area] would do the same."

In the meantime, residents of Mercer, Ocean, Hunterdon, Warren and Monmouth Counties will continue to pick and choose.

At the BC Sports Collectible store in the Quaker Bridge Mall, along Route 1, just south of Princeton, the display window contained a Brian Dawkins throwback jersey, an autographed Brian Westbrook photo and a shot of Sheldon Brown's infamous hit on Reggie Bush alongside a Peyton Manning jersey, and signed photos of the Giants' Justin Tuck and David Tyree.

"I'd say that the stuff we sell is split 50-50, Eagles and Giants," said Dan Seigle, the store's manager.

Seigle places the line separating the two teams' fans as somewhere near where Interstates 295/95 crosses Route 1.

Fans in the demilitarized zone, according to Chenoski, often resemble Philadelphia and New York fans elsewhere. Eagles supporters tend to be more blue-collar and more passionate about their favorite team. Giants fans, he said, like most North Jerseyans, lead faster-paced lives.

"Whether it's driving or drinking coffee, they just move more quickly," he said. "I used to DJ down near Cape May. It was very low-key. But when I moved up North, everyone wanted to know what kind of special equipment I had. And when they heard my asking price, they said I should have been insulted to ask for so little."

When Eagles fans consider North Jersey, he said, they bring up traffic, mobsters and heavy industry. Considering their own region's attributes, they like to refer to the Shore, the farm produce and the Pinelands.

Giants fans, meanwhile, often view their southern counterparts as culturally deprived hicks, while they point with pride to their mass transit, their arts scene and their more upscale economy.

Perhaps the biggest factor in creating Eagles and Giants fans is an individual's media choices. Central Jersey residents like to believe they have the best of both worlds.

"I've always said the people in the Trenton area have the greatest media choices of anyone in the nation," Chenoski said. "They get the New York and Philadelphia TV and radio stations. They can get The Inquirer, the New York Times, the Star-Ledger, the Trenton Times or the Trentonian.

"It's great to have so many choices."

Contact staff writer Frank Fitzpatrick at 215-854-5068 or ffitzpatrick@phillynews.com.