The state was one of the most contested in the United States in the 2008 election as Republican John McCain spent considerable time and money trying to win Pennsylvania's 20 electoral college votes, a substantial chunk that places it second only to Florida among swing states.
And the 2010 mid-term elections gave the Grand Old Party reason to hope that, for the first time since 1988, the working-class state of almost 13 million people might elect a Republican president.
Pennsylvanians cast their ballots just two years ago for a Republican governor, Tom Corbett, who won the most decisive victory of any Republican in the state's history. Republicans also seized a U.S. Senate seat and control of the Pennsylvania legislature.
And except for Obama's 11 percentage point advantage over McCain in '08, most presidential victories have been razor-thin in Pennsylvania.
Yet neither Romney nor Obama has been campaigning much in the so-called Keystone State, although a pizza parlour crowd in this working-class city was still buzzing recently about First Lady Michelle Obama's appearance the night before in nearby Bethlehem, where she urged the crowd to get out and vote for her husband on Nov. 6.
The Obama re-election team has spent little on advertising here; Romney's has doled out nothing. In 2008, on the other hand, Obama and McCain spent US$41 million advertising in Pennsylvania, more than in any other state but Florida.
Change may be afoot, however, in the wake of a new poll indicating that Romney is narrowing the gap in Pennsylvania.
Willie Nash, a lifelong resident of Allentown, is fretful at the notion of an ascending Romney.
"I don't like Romney, and I sure don't think he likes me, if you know what I mean," says Nash, an African-American, as he noshes on a pepperoni slice and sips a Yuengling during his lunch break from a nearby medical centre, now the biggest employer in the former manufacturing town.
"Obama might not have done the job we all hoped he would, but he's a lot better for people like me, and the rest of us in the so-called working class, than Romney will be. And I think if Obama gets a second term, he'll get to work doing everything he said he'd do."
In the latest poll by Franklin and Marshall College in Lancaster, about 100 kilometres southwest of Allentown, Obama was still leading Romney by six points, at 44 per cent to 38 per cent among registered voters. But the same survey had Obama 12 points ahead of Romney in June.
Romney is winning over white working-class voters and retirees, while Obama has the support of college-educated Pennsylvanians, minorities, women and younger voters. The Republican presidential hopeful, however, now gets higher marks on the economy, a reversal from the June poll.
The race, indeed, is tightening in Pennsylvania in recent weeks and it's due almost entirely to the economic concerns of the state's blue-collar workers, said Terry Madonna, the Franklin and Marshall pollster and a political science professor.
"The real problem for Obama here is the lingering nature of the recession, and even though economists will say it's not a recession, you can't tell Pennsylvania voters that," Madonna said in an interview.
"His other real problem is his low job performance rating, which is reflecting a belief that he's not got a handle on the economy."
The addition of Paul Ryan to the Republican ticket may spell good news for Obama in Pennsylvania, however. Ryan's proposals to privatize Medicare, a cherished American government program, aren't expected to play well among the state's large population of senior citizens.
Romney is waiting until after the Republican National Convention, which kicks off next weekend, to decide how hard to fight in Pennsylvania, Madonna said. That's when he'll be able to start spending money raised for the general election; Team Obama will likely respond in kind.
"Moving forward, Romney's really going to have to decide what to do here," Madonna said.
"He's not putting up a nickel of his own money, not a dime, into television advertising in Pennsylvania. The president has spent some money here, and his SuperPAC spent US$7.2 million. So we're all waiting to see — if the race continues to tighten, what does the Romney camp do?"
There are other factors, one particularly positive for Republicans, that may influence Romney's deliberations on Pennsylvania in the weeks to come.
Commonwealth Court Judge Robert Simpson allowed a Gov. Corbett-backed law requiring voters to show ID before casting ballots to take effect this election day. Democrats and civil rights groups have said the law will essentially prevent countless Pennsylvanians from voting — many of them minorities who favour Obama, and also the poor and the elderly.
Simpson, a Republican, said those who challenged the law failed to prove it violates the state's constitution by infringing upon the rights of voters. There's plenty of time for voters without ID to obtain it, he added.
The Pennsylvania Supreme Court will hear an appeal of the case soon. The six-member court — one justice is suspended — is evenly divided between Democrats and Republicans.
Judith Browne-Dianis, co-director of the Advancement Project, one of the organizations challenging the law, railed against Simpson's ruling.
"Pennsylvania's voter ID law erects an unequal barrier to voting for hundreds of thousands of eligible voters, disproportionately blocking veterans, seniors and people of colour from the polls," she said in a statement.
Others have suggested as many as a million voters could be effectively disenfranchised — and presidential elections in Pennsylvania have often been decided by margins of less than a million voters.
Perhaps that's why Michelle Obama recently took to a college gymnasium to rally Democratic voters as she emphasized her and the president's working-class roots.
"Barack has said this election will be even closer than the last one," she told the crowd of about 2,400 cheering fans in Bethlehem.
"This election could come to those last few thousand votes, particularly in this state. When you think of a few thousand votes spread out across the state, that could be the one new voter that you register, that one neighbour you get to the polls. That could be the difference. That could be the one that puts us over the top."
She also aimed an apparent shot at Romney's silver-spoon upbringing.
"Barack knows what it means to be in the struggle," she said.
"He knows what it means to work hard because you want to give a better life to your kids. And when you walk through that door of opportunity, you do not slam it shut behind you. That's what's at stake in this election."
Madonna, indeed, said he still believes Romney faces an enormous uphill battle in Pennsylvania, despite his improving poll numbers, due to his low likeability ratings.
"He hasn't given people in the state a reason to vote for him," Madonna said.
"If you look at past elections, Obama should lose. On the economy, he's doing worse than George W. Bush, than Jimmy Carter, than Gerald Ford. But he's still personally popular. And Romney has been unable to convince people that he's a viable alternative — he has still not made the sale."