BRYN MAWR, Pennsylvania (AP) — The Democratic National Convention is heading to Philadelphia, but Hillary Clinton has her sights set just beyond the city limits.
Pennsylvania's 20 electoral votes will probably hinge on Philadelphia's suburbs. No presidential candidate in 40 years has carried the state without winning the overall vote in the four-county arc just outside the City of Brotherly Love.
From the oil refineries in southern Delaware County to the 18th-century barns north in Bucks County, the suburban collar has grown over time to account for more than one-fifth of all Pennsylvania voters. In the past decade and a half, its political profile has shifted from decidedly Republican to narrowly Democratic.
For that reason, the presumptive Democratic presidential nominee and her allies are trying to gain ground in the state, which Democrats have carried for the past six elections, in what could be a tight general election with Republican Donald Trump.
"Anecdotally, that creates a challenge for Trump," said Philadelphia-based Democratic strategist Mark Nevins. "He needs to appeal to the thoughtful moderates in the suburbs."
Today, registered Democrats in the four-county region outnumber Republicans by roughly 52,000. That's quite a change from 2000, when the GOP registration edge was 357,000.
"As people have moved away from Philly, they have tended to be the more progressive voters," Nevins said.
Clinton may not see the historic vote totals won by Barack Obama in Philadelphia back in 2008, but she probably will match or exceed his suburban vote, said former Gov. Ed Rendell, D-Pa.
Obama turned out Philadelphia's black voters by overwhelming margins in 2008 and 2012. He also carried the suburban counties both times, albeit by fewer votes in 2012 than four years earlier, the result of economic discontent, said Rendell, a former Philadelphia mayor.
Clinton's campaign is targeting suburban Republicans turned off by Trump. He will gain in some white, blue-collar pockets of Philadelphia and its suburbs.
"But Hillary is more popular in the Philadelphia suburbs in 2016, than Obama was in 2012," Rendell said, predicting her share of the suburban vote to exceed the president's.
Trump's tough talk on trade deals and building a wall on the U.S.-Mexico border falls flat with Nicola Fryer, a 43-year-old Republican from Media, in Delaware County. He may be tougher on enemies abroad, Fryer said, but she worries that Trump will ruin relationships with U.S. allies.
"He doesn't know what he's doing," said Fryer, rushing between her office and picking up lunch in Bryn Mawr's bustling commercial strip. "What would he get us into? I don't trust him at all."
Trump has said he can compete in Pennsylvania as he maps a way to the 270 electoral votes needed to clinch the presidency. He points to GOP primary election victories in Indiana, Michigan and Pennsylvania as evidence.
Winning Pennsylvania and other Rust Belt state such as Wisconsin and its 10 electoral votes, could offset a loss in Florida, which offers 29.
Not since 1976 has a presidential candidate captured Pennsylvania without winning the collective four-county vote in Philadelphia's growing suburbs. According to census data, the four suburban counties have higher employment rates, higher family incomes and higher proportions of college graduates and foreign-born citizens than Pennsylvania as a whole.
In recent decades, the suburban population has risen while most other areas in the state have declined. The influence of the suburban vote on statewide elections has increased, from 18 percent in 1976 to 22 percent in 2012.
While Democratic presidential candidates have carried the state in six consecutive elections, the race is competitive, with less than four months until the November vote. A Quinnipiac University poll published July 13 shows Trump ahead of Clinton by 2 percentage points. Other recent polls have shown Clinton with a lead in the single digits.
Though Clinton's campaign has spent relatively little advertising in Pennsylvania, the pro-Clinton group Priorities USA began advertising on television last month, having first left it off its list.
For now, the group is airing an ad that includes the parents of a Columbus, Ohio, girl with a disability, highlighting negative remarks by Trump last November about a news reporter with a disability. The ad features the girl's parents seated on a sofa in a homey setting expressing outrage at Trump.
The group has reserved $10 million in advertising through the election, just behind Colorado, but well behind Florida and Ohio, which are viewed as more critical, and with more expensive media markets.
"We're going to do everything we possibly can to keep Donald Trump from becoming president," Priorities USA spokesman Justin Barasky said. "That means we're constantly reassessing the dynamics of the race."
Beaumont reported from Des Moines, Iowa. Associated Press writer Julie Bykowicz in Washington contributed to this report.
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