Not content with being the top-grossing casino in the state, Parx wants to grow again - just three months after opening a bigger $250 million gambling hall in Bensalem.

The casino is embarking on a multiphase expansion over the next three to five years at a cost of $100 million - with the potential to add $200 million more - depending on the size of a hotel, spa, and showroom, according to Bob Green, chairman of Greenwood Racing Inc., which owns Parx.

He said the expansions could create an additional 1,000 jobs over that time.

"We have never rested on our laurels," said Green, who revealed his casino's growth plans yesterday. "We are always looking to improve our business. Businesses have to evolve and invest in the future."

Green said the first phase of expansion, planned for July, would be 80 table games, including blackjack, craps, roulette, and mini-baccarat in the new casino.

An additional 20,000 square feet will be added in December for another bar, 450 additional slot machines, and 40 more table games.

By next spring, 30,000 square feet will be added for two restaurants and a nightclub. The number of slot machines will reach 4,000 and table games will peak at 140.

Green also plans a 400-room hotel to be constructed in the next two to three years.

"If we see a need for other entertainment facilities and potential residential accommodations and retail, we will pursue them," he said. "There's a whole raft of potential development opportunities out there."

Green attributed the passage of table-games legislation in early January as the catalyst for the expansions, but also the strong customer response since the new casino opened Dec. 17. Parx sits next to its predecessor, the old PhillyPark Casino and Racetrack, built for $120 million, on a 450-acre tract that Green owns.

Located in Lower Bucks County, with acres of surface parking, Parx has been the undisputed revenue champ in Pennsylvania since debuting in mid-December 2006. Its customers are from Bucks, Northeast Philadelphia, and central New Jersey.

The casino, which currently has 3,294 slot machines, continuously outperforms its much bigger and costlier counterparts, namely Sands Resort Casino in Bethlehem and Rivers Casino in Pittsburgh, both of which cost nearly $800 million each to build - just over three times more than Parx.

From March 15 to 21, the casino's gross slots revenue was $8.6 million - tops among the state's nine casinos by far. The state has a 55 percent tax rate on slots revenue, and will tax table-games revenue at 14 percent.

The second-closest in revenue was Harrah's Chester Casino and Racetrack in Delaware County, which pulled in $6.2 million.

Hollywood Casino near Harrisburg, which cost roughly the same as Parx (at $250 million but with 927 fewer slot machines) made $5.5 million, while Sands Bethlehem (with 3,192 slots) and Rivers (with 3,000 slots), each generated $4.9 million.

"Parx has an outstanding location in a demographically attractive area, excellent access, abundant parking, and a management team that knows how to compete from its rich experience in Atlantic City," said analyst Joseph Weinert of Spectrum Gaming Group L.L.C. in Linwood, N.J. "And now, with a significantly better physical product, this casino is on pace to become one of the country's slot powerhouses."

Contact staff writer Suzette Parmley at 215-854-2594 or sparmley@phillynews.com.