The telephone survey of 601 likely voters, conducted from Tuesday through Thursday, had a statistical margin of error of plus or minus 4 percent. The results, which include firmly committed supporters and those leaning toward one candidate or the other, are comparable to those of other recent polls, including one released Thursday by Muhlenberg College, which also had Obama leading by nine points in the state.
Jeffrey Plaut of Global Strategy Group, a Democratic polling firm, said the results may indicate Pennsylvania has lost some of its "swingy-ness." He said Friday that Democrats would have to fail to turn out their base voters to "put the state in play."
His survey partner, Republican Adam Geller of National Research Inc., said Romney clearly was behind in the state. But he said Obama's current lead could be less - perhaps six, five, or four points - in light of the margin of error and the proven tendency of undecided voters ultimately to vote against incumbents.
"Maybe if Romney decided to spend more time and resources in the state of Pennsylvania, the state certainly could be in play," Geller said.
Barely half of poll respondents approved of the job Obama has done as president, a finding that Romney could build on, Geller said. He said he expected the race to tighten.
But only about four in 10 respondents had a favorable view of Romney, who, starting with this week's Republican National Convention, must burnish a personal image tarnished by a summer's worth of negative Obama ads.
Romney's choice of Rep. Paul Ryan of Wisconsin as his running mate does not appear to have given him a Pennsylvania boost. Plaut said the numbers showed Romney might have done better here if he had picked Gov. Christie, who has a strong favorability rating across the Delaware from his home turf.
Plaut said it was significant that 57 percent of poll respondents said they believed Obama would win Pennsylvania and its 20 electoral votes; only 29 percent said they thought Romney would. That expectation could become self-fulfilling if it influences Election Day turnout.
The country's sixth-largest state, Pennsylvania has not favored a Republican for president since 1988, when it picked George H.W. Bush over Michael S. Dukakis.
Yet with its combination of East Coast and Midwest influences, its two big cities and myriad small towns, its union halls and farmers' markets, Pennsylvania has appeared a ripe target for both major parties every four years.
The state is heavily Democratic in voter registration, but has both a Republican governor and a Republican legislature. Its voters have a history of party switching and ticket-splitting.
A solid majority of those polled said they thought the state and the nation were on the wrong track.
On average, they gave the economy of Pennsylvania a grade of D-plus; they gave the nation's roughly a D.
A year from now, voters said, they expected both the national and state outlook to be in the C range.
Most gave their own economic situation fair to poor grades. But a majority were optimistic that their situation would be slightly better a year from now.
The poll gave Obama a substantial lead among women; he was statistically tied with Romney among men.
One poll participant, Mary Hughes, a Democrat from Philadelphia's East Mount Airy section, said in a follow-up interview Friday that it was easy to explain the so-called gender gap.
"Mr. Obama has tried to show that he cares about women and women's rights," said Hughes, 70, a registered nurse. "This is more than what I'm hearing from Mitt Romney and the Republicans in general."
Obama led among all age groups, with his strongest edge among those 45 to 64. He led among those with a college education and those without.
Eighty-five percent of black respondents said they would vote for Obama. Among whites, the split was 46 percent for Obama and 47 percent for Romney, a statistical tie.
More than any other factor, geography shaped the results.
Obama's lead was largely built on his strength in Philadelphia, the state's largest city, in which he was ahead by almost 8-1.
In the crucial suburbs of Bucks, Chester, Delaware, and Montgomery Counties, all of which voted for Obama in 2008, he led by just three points. That is well within the higher margin of error, plus or minus 8.6 percent, for polling in those four counties.
Andrew Reilly, the Republican chairman of Delaware County, said he was not surprised that Romney trailed in the state.
Many voters who don't like Obama have not gotten to know Romney yet, he said. They will do so, starting this week with the GOP convention, he said.
"People know Obama; they have made the decision they are looking for an alternative," Reilly said Friday. "But Romney has not made the sale that he is that alternative. He has to make the sale."
Too late, said Marcel Groen, veteran Democratic chairman of Montgomery County. He said many suburban voters had already made up their minds that the Republican Party had moved too far right for them.
Groen noted the recent comment by Rep. Todd Akin, a Missouri Republican Senate candidate, that women rarely get pregnant from "legitimate rape." He said that notwithstanding Akin's later apology, the comment had helped solidify an impression "that elements of the Republican Party have declared war on women."
Suburban voters - especially women - tend to be moderates, Groen said. They want "solutions," not "ideology," he said, and right now the Republicans seem more ideological.
Poll participant Nick Polidori, 64, of Glenolden, Delaware County, said that America's future prosperity depended on the economy growing and that only Romney had faith in American enterprise.
"I like what he wants to do to try to create jobs and the tax breaks he wants to give and all," Polidori, a Republican, said.
As a retired postal worker, he might not need a tax break as much as some. But, he said, "my children will and my grandchildren will."
Hughes, the nurse from Philadelphia, who said, "I vote every single time," said she did not think much could draw her to Romney between now and when she casts her vote Nov. 6.
"He's not a people person," she said. "He's more focused on the guys who make a lot of money and their wishes. He could care less about the middle guy."
Another Obama fan, Michael Hafter, a software architect from Narberth, Montgomery County, said Republicans were fooling people in promising to cut the deficit without tax increases.
Obama "is less of a bald-face liar than Romney," Hafter said. "He appears to have math skills, whereas Romney and Ryan believe in voodoo for numbers, and [Obama] speaks honestly when he says people have to pay taxes."
In Chester County, first-time presidential voter Dane Hill said he will cast his lot with fellow Republican Romney. Hill, 21, of Chadds Ford, said he was not against Obama but believed Romney knew better how to jump-start the economy. He said jobs were important to a person such as himself, who will graduate next spring with a degree in human development and family studies from the Brandywine campus of Pennsylvania State University.
"Romney has a drive to succeed," Hill said, "and he wants to turn this country around."
Contact Tom Infield
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