HARRISBURG -- Politicians don't usually tout new or higher taxes while running for office. But Democratic gubernatorial candidate Dan Onorato thinks his support for an extraction tax on Marcellus Shale gas will be a political plus in his race against Republican Tom Corbett.

Mr. Onorato told reporters here Wednesday that the Legislature should enact a severance tax on natural gas to pay for damage to state roads and bridges caused by heavy trucks and other equipment used by gas drillers and to restore the 28 percent budget cut that the state Environmental Protection Department has suffered in the last two years.

Mr. Onorato, Allegheny County executive, also wants to use the shale gas tax revenue to replenish the state's Growing Greener program, which preserves farms and undeveloped land and restores old industrial sites called brownfields.

Mr. Onorato noted that Mr. Corbett, the state attorney general, has said he opposes any new tax or tax increase. This means, Mr. Onorato said, that state and municipal governments will have to take money from their budgets to pay for the damage caused by drilling companies and to protect greenfields.

"Tom Corbett wants taxpayers to foot the bill for protecting the environment, while I want the drillers to pay for it," Mr. Onorato said. "He has made clear that his single goal is to prevent the oil and gas companies that are making hundreds of millions of dollars a year drilling in Pennsylvania from paying their fair share."

However, Mr. Onorato did pledge opposition to increases in the state sales tax, personal income tax and gasoline tax.

Mr. Onorato refused to divulge two key details about a Marcellus Shale severance tax -- the tax rate on the gas that's pumped out from deep underground and how much money he wants the tax to generate.

Gov. Ed Rendell has talked of putting a 5 percent tax on the value of the extracted gas, plus a levy of 4.7 cents per thousand cubic feet of gas, to generate about $100 million a year.

Other officials favor a tax only on the volume of gas produced, but at a rate high enough to produce about $200 million a year.

Mr. Rendell has called on the Legislature to enact a severance tax by Oct. 1, one that will produce $70 million this fiscal year and help close a $282 million budget hole. Mr. Onorato said he wouldn't use the severance tax money to balance the state budget.

He claimed Mr. Corbett's opposition to a shale gas tax may be rooted in the large financial support he's gotten from the industry since 2001. Mr. Onorato said that a citizens lobby called Common Cause disclosed in May that Mr. Corbett received $361,000 from energy companies while Mr. Onorato got $59,000.

Mr. Onorato's call for a shale tax is a change from what he said at a Democratic gubernatorial candidates' meeting in January, when he was undecided about the levy.

Corbett spokesman Kevin Harley said Mr. Onorato has changed his mind about the shale tax because of the views of "his mentor, Ed Rendell."

"Tom Corbett is opposed to raising new taxes. Lowering taxes increases job growth and expands the economy," Mr. Harley said.

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