Pennsylvania may determine who wins the presidency Nov. 2, and suburban women may determine who wins Pennsylvania.

Philadelphia's four "collar counties" — Bucks, Chester, Delaware and Montgomery — are predominantly Republican but voted for Democratic Gov. Ed Rendell (search) in 2002. Surveys taken before last week's debate showed President Bush running better in the vote-rich suburbs than four years ago.

Such improvement, Rendell said last month, was "because of the effective job Republicans did on national security and terrorism." More recently, Democrat John Kerry (search) has sharpened his criticism of Bush's Iraq policy and turned in a solid debate performance. A new Keystone poll gives Kerry the edge in the state, and private Democratic and GOP polls show Bush losing ground in the suburbs, particularly among women.

"It just doesn't get any closer than this," said G. Terry Madonna, a professor and pollster at Franklin & Marshall College in Lancaster. Bush narrowly lost the state to Democrat Al Gore in 2000, and Kerry can't afford to let it turn GOP.

For many suburban women, the question is whether to support a president who they believe is tough on terrorism or the challenger who is raising questions about Bush's credibility and Iraq.

Rendell and others say Kerry's support for abortion rights, a ban on certain semiautomatic weapons and expanded federal support for stem cell research can appeal to moderate women in the Philadelphia suburbs. Last month, when Kerry was trailing in polls, Rendell complained that the candidate's consultants in Washington were not listening to his advice.

The votes of women aren't all that matter in the nation's sixth most populous state, which has 21 electoral votes. Republicans are trying to find new voters statewide among Bush's conservative, churchgoing base. In one poll, nearly one-quarter of his supporters listed family and moral issues as uppermost in their minds.

Bush's team also hopes to whittle customary Republican deficits around Pittsburgh, where suburban shopping malls sit on land once occupied by steel mills.

BY THE NUMBERS:

9,412 — Voting precincts in Pennsylvania.

47,000 — Signatures Ralph Nader's campaign submitted to get him on Pennsylvania's ballot as an independent presidential candidate, prompting a challenge that is the focus of a court fight.

70,000 — Guitars C.F. Martin & Co. in Nazareth will make this year.

QUOTABLE:

— "Bush thinks the economy is great. I don't. ... Kerry's a little better that way, but I think Bush is better for the war on terror, a little stronger." — Bob DuBois, 40, a federal employee from Delaware County and a registered Republican who says he has not decided which candidate to support.

— Kerry "is a blabbermouth. He's been talking about Vietnam as if he was the only one there." — James Dougherty, 70, a retiree from Philadelphia and a registered Democrat who says he will vote for Bush.

— "If we can pull out of Iraq slowly, the money being used to support the war can be used to support the domestic economy." — Aissia Richardson, 38, of Philadelphia, a fund-raiser for a local nonprofit group and a registered Democrat who plans to vote for Kerry.

NOTABLE:

In the past half-century, Pennsylvania has picked the winning candidates in all but two of the 13 presidential elections. The most recent exception was in 2000, when Democrat Al Gore carried the state but Bush won his first term. When Richard Nixon was first elected in 1968, Pennsylvanians preferred Democrat Hubert Humphrey.

WHAT TO WATCH ON ELECTION NIGHT:

Pennsylvania strategists for both Bush and Kerry describe the Philadelphia suburbs as the crucial swing region within the swing state. The suburbs use a hodgepodge of vote-counting systems that include punch card, lever and touch-screen machines. During the April 27 primary for U.S. Senate, a Bucks County computer foul-up initially overcounted ballots by thousands, holding up an accurate statewide tally until late in the night.

IN PENNSYLVANIA FOUR YEARS AGO:

Despite conventional wisdom that young voters generally favor Democratic candidates, Bush won over Pennsylvania's whippersnappers in 2000. Nearly half — 49 percent — of state voters 18 to 29 picked Bush, compared with 44 percent for Gore. But the Democrat handily won the elderly vote — a crucial bloc in a state that has one of the oldest populations in the country.