HARRISBURG - Gov.-elect Tom Wolf has begun filling key positions on his senior staff roster, turning to former coworkers and onetime rivals for his new job.

Wolf on Wednesday named John Hanger as his secretary of policy and planning, a high-profile job that involves helping the governor craft and realize policy priorities.

Hanger, 57, of Hummelstown, was secretary of environmental protection under Gov. Ed Rendell and briefly ran against Wolf in this year's Democratic primary campaign. Wolf also worked for Rendell, heading the Department of Revenue.

Wolf said Mary Isenhour, a high-level strategist in his campaign, will be his secretary of legislative affairs, a job that will require navigating the politically tricky landscape within the Republican-dominated legislature.

"It will be a big challenge," said Isenhour, 56, of Harrisburg. "I believe that legislators, Republicans and Democrats, are ready to get things done."

The governor-elect tapped Obra S. Kernodle IV, 36, a Philadelphian who has worked for Mayor Nutter and other city Democrats, as his deputy chief of staff and director of the Office of Public Liaison.

"In every executive position I've held, I've been successful because I surrounded myself with really bright, capable people," Wolf said Wednesday. "This is an amazing chance to make a really great state better and get it back on its feet . . . and the people who I've chosen are willing to be inspired by that."

Wolf, who will be sworn in next month, already named Katie McGinty as his chief of staff. McGinty, a Philadelphia native, was a DEP secretary under Rendell. Like Hanger, McGinty ran for the Democratic nomination for governor this year. Hanger dropped out of the race; McGinty lost.

Hanger has spent much of his career in environment and energy policy, inside government and out. He served as president of Penn Future, the statewide environmental advocacy group, and as a member of the Public Utility Commission, he campaigned for legislation expanding alternative energy use and stronger environmental-protection laws.

During the campaign, Hanger made one of his central issues the legalization of medical marijuana.

Hanger has clashed with Republicans in the legislature over environmental policy and drawn fire for his support of natural gas drilling, most notably when he walked out on an interview with the director Josh Fox that was included in Fox's 2010 anti-fracking documentary, Gasland.

Gas industry leaders praised Hanger's appointment. "Mr. Hanger absolutely understands the clear and undeniable benefits tied to responsible shale development," said Dave Spigelmyer, president of the Marcellus Shale Coalition. "We congratulate him on this new role and look forward to working collaboratively with him, as we did during his tenure as DEP secretary, where he was a strong natural gas advocate."

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