In its first major move in support of a candidate in Pennsylvania this election cycle, the Koch family-backed Americans for Prosperity announced Thursday that it will support Republican Scott Wagner in his campaign to unseat Gov. Wolf this November.

The self-proclaimed grassroots free-market advocacy group, deeply entrenched in conservative politics, said in a statement it will canvass, make phone calls, and run paid advertisements backing the Republican nominee while highlighting the "failed policy record" of the Democratic governor.

Beth Anne Mumford, the group's Pennsylvania director, said Wagner's record "reflects strong leadership on causes our activists champion." The Republican has based much of his campaign on making Pennsylvania more friendly to businesses, in sync with AFP's fights to lower taxes and restrain the influence of government over the economy. Wolf has failed to abide by those principles in his first term as governor, Mumford said.

"Wolf's lack of leadership has instead left the commonwealth with a legacy of bigger government, higher taxes, and runaway spending that consistently stifles economic dynamism," she said.

The Wolf campaign said the endorsement proves Wagner is in thrall to special interests.

"These big oil and gas barons are trying to buy the election for Scott Wagner so he can continue to give handouts to billionaires like the Kochs by blocking a severance tax and refusing to make big corporations pay their fair share," campaign spokesperson Beth Melena said.

With three field offices in the state and a half-dozen paid staffers, Americans for Prosperity hopes to replicate the success it had in 2016 when it spent more than $1 million helping defeat Pennsylvania Democratic Senate nominee Katie McGinty, who lost to Republican Sen. Pat Toomey in what ended up being the most expensive Senate race in the country. During that effort, volunteers knocked on more than 135,000 doors and made 2.4 million phone calls.

The group did not signal how much it would spend in support of Wagner, but with 13 weeks left until the election, but it said dozens of volunteers will deploy from AFP offices in the Erie, Harrisburg, and Philadelphia areas to canvass for him.

Wagner "is pleased to have the support of an organization committed to promoting business-friendly policies and fostering economic growth," campaign spokesperson Andrew Romeo said Thursday. He said Wolf "is bought and paid for by the public sector unions."

Americans for Prosperity's backing could send a jolt of energy into Wagner's fundraising, which has lacked the support of some key establishment Republicans in Pennsylvania. As of June 4, Wagner had $1.6 million on hand, trailing the incumbent by a factor of nearly 10-1.

His campaign account could also see a boost from supporters of President Trump, after the president praised him in a campaign visit for Republican U.S. Senate hopeful Lou Barletta last week. Wolf used the president's endorsement of his opponent as a fundraising plea.

Wagner trailed Wolf by double digits in two polls released in June, but his campaign alleged one of those oversampled Democrats.

Americans for Prosperity, known for more than a decade for its backing of conservative candidates, has said it is "raising the bar" — looking for policy agreement, not party affiliation.

But this renewed focus has clashed with some Republicans recently, including Barletta, who was targeted in May over his vote on the $1.3 trillion spending bill two months earlier as part of a mail and ad campaign criticizing 17 House members from both parties for voting to increase waste and spending.

Julian Routh: jrouth@post-gazette.com, 412-263-1952, Twitter @julianrouth.