PHILADELPHIA — Potential Presidential contenders Hillary Rodham Clinton and New Jersey Gov. Chris Christie will be campaigning in the Philadelphia area Oct. 9th for Pennsylvania’s gubernatorial candidates, as they compete in the state’s voter-rich southeast corner.

Christie planned an afternoon appearance at a rally in Wayne for Republican Gov. Tom Corbett. Christie chairs the Republican Governors Association, a fundraising arm that helps the GOP’s gubernatorial candidates around the country. The association is Corbett’s biggest campaign donor at $5.8 million so far in this campaign cycle.

Clinton will headline an evening Women for Wolf rally at the Constitution Center in downtown Philadelphia to help Corbett’s Democratic challenger, Tom Wolf.

A high voter turnout in Philadelphia would favor Wolf. Almost 80 percent of the city’s 1 million-plus registered voters are Democrats, although just 40 percent cast a ballot for governor in 2010, when Corbett won his first term by 9 percentage points. Voter turnout in the rest of the state was 48 percent that year.

Meanwhile, the candidate who wins Pennsylvania’s four heavily populated suburban counties is nearly assured of a victory. Pennsylvania has nearly 8.3 million registered voters, and one in three lives in Philadelphia or its suburban counties.

Independent polls show Wolf with a comfortable lead over Corbett, as the campaign spending threatens to break Pennsylvania’s record of $69 million.

Corbett is Pennsylvania’s former two-term Attorney General from the Pittsburgh area. Wolf, a first-time candidate, ran his family’s York-based building products distribution business for much of the last three decades.

Christie has been in Pennsylvania three times already since June to raise money or campaign for Corbett. Clinton’s visit is her first in support of Wolf, one of several gubernatorial campaigns she is giving her stamp of approval to this fall.

At a women’s event held by the Democratic National Committee in September, Clinton promoted Wisconsin Democrat Mary Burke. Clinton has raised money for the Democratic Governors Association, and headlined a Florida fundraiser earlier this month for Charlie Crist.

Clinton was in Chicago on Oct. 8 to aid embattled Illinois Gov. Pat Quinn, before heading to Philadelphia.

Clinton’s schedule before the Nov. 4 election includes stops for Martha Coakley, who is seeking the Massachusetts governor’s post, and for New Hampshire Gov. Maggie Hassan.

Christie also is beating a path across the states holding gubernatorial races. He campaigned last week for Bob Beauprez in Colorado; on Oct. 6 for Tom Foley in Connecticut; and on Oct. 8 with Gov. Rick Scott in Florida. Christie is expected in Rhode Island on Oct. 10 to campaign for gubernatorial candidate Allan Fung and next week in Maine for Gov. Paul LePage.