HILADELPHIA - Vice President Al Gore, shouting over the background noise of cheers and thumping drums at a late Saturday night rally here, described the situation succinctly: ''Pennsylvania will decide who the next president will be,'' he predicted.
In the next breath, he added, ''Philadelphia will decide what Pennsylvania will do.''
Of all the contests for electoral votes this fall, none rivals the fight for Pennsylvania. With Gore holding the advantage in California and New York and Governor George W. Bush commanding a big lead in his home state of Texas and a smaller edge in Florida, both sides are throwing every available resource into the nation's fifth-largest state, where the race is believed to be extremely close.
Gore strategists, who have been counting Pennsylvania's 23 electoral votes in their column for weeks, say privately that it will be virtually impossible for the Democratic candidate to win without the state. But if Pennsylvania goes to Gore, they say, it portends victories in a vital swath of industrial states including New Jersey, Michigan, and Illinois.
Sensing an opportunity to stop Gore here, the Bush campaign is committing millions of dollars and thousands of hours of manpower to Pennsylvania.
''We were down by a considerable margin two or three weeks ago,'' said Leslie Cromis, executive director of Pennsylvania Governor Tom Ridge's Leadership Fund and chairman of a four-state region for Bush. ''We've slowly chipped away. The tracking polls each night show us anywhere from 2 points up to 2 points down.''
The Philadelphia Inquirer reported Sunday that Pennsylvania ''ranks first in the amount of cash the candidates and their parties have spent on TV ads.'' The figure was $16.9 million through Oct. 13. A study by the Brennan Center for Justice at New York University found that more television commercials were playing in Philadelphia than in any other market in the country.
Philadelphia television stations cover not just the heavily-populated southeastern corner of the state. Their range extends to the neighboring states of New Jersey and Delaware, where the presidential race is also close.
Philadelphia, a Democratic city of 2 million, has historically provided the firepower for any success by Democrats in the state. President Clinton won margins of more than 300,000 in the city both times he carried Pennsylvania.
But the suburbs that sprawl for dozens of miles outside Philadelphia have been considered Republican country for years. Gore is trying to change that.
MarDee Xifaras, the Massachusetts Democratic National committeewoman who is directing Gore's Pennsylvania operation, said the campaign is ''emphasizing the bread and butter issues - prescription drugs, Social Security, and home heating oil'' in an effort to reach out to suburban voters.
Using the same issues, the Gore campaign is also targeting the Scranton-Wilkes-Barre area north of here, where a strong antiabortion movement has often discouraged Democratic candidates.
''I think - I hope - we'll have the advantage of a final-push operation with literally thousands of people around the state,'' Xifaras said. Drawing on labor unions and black political organizations in Philadelphia, the Democrats have a built-in, get-out-the-vote network that will be augmented by thousands of volunteers. ''A field operation can be worth 1-to-3 percent on election day,'' she said.
Cromis acknowledged that demographics have shifted in the state. ''The southeast suburbs have become more independent,'' she said, making the Republican task harder. At the same time, Cromis said, traditional Democratic counties around Pittsburgh are ''becoming more conservative and Republican.''
The Bush campaign is strengthened by a statewide organization led by Ridge, a governor who enjoys high favorability ratings. Ironically, the struggle for Pennsylvania probably would not be taking place if Bush had chosen Ridge as his running mate.
In early summer, Ridge appeared to be a leading contender for the vice presidential nomination. Not only would he be able to deliver Pennsylvania, Ridge's support of abortion rights would also broaden the Republican ticket's national appeal, it was thought. But the conservative, anti-abortion bloc in the GOP opposed him.
After Bush chose Dick Cheney, moderate Republicans and independents reacted adversely in the Pennsylvania suburbs, according to Neil Oxman, a Democratic consultant in Philadelphia. ''They wondered just how right-wing this guy Bush is,'' Oxman said.
This week, as Ridge joined other Republican governors in a barnstorming tour of the country, his forces were engaged in all-out warfare to salvage his own state for Bush.
Cromis was asked, was this intense battle necessary? ''You'll have to ask the folks in Austin that,'' she replied.
