In an interview with the far-right radio host John Fredericks, Mastriano named three counties that were being targeted — Philadelphia, Tioga and York — and said they might do a “round two” of counties. A Philadelphia official confirmed to POLITICO that it had received a letter from Mastriano but declined to comment further. An official in York also confirmed that the president of the elections board there also received a copy of the letter, and the Tioga solicitor also confirmed the county recieved the request but declined to elaborate further.

Mastriano’s office did not respond to a series of questions from POLITICO.

Mastriano's push is inspired by a similar effort in Arizona, which recently concluded its review of millions of ballots from Maricopa County. The Arizona push, led by the GOP-controlled state Senate, is referred to by proponents as an “audit” — but election professionals and local and state election officials nearly universally deride it as an unprofessional fishing expedition that doesn’t rise to the standards of an actual audit. Mastriano had traveled to Arizona to view that review, praising the effort.

“My goal is to do similar to what we saw in Arizona, in that every ballot is photographed and magnified, and we can determine what ballots were filled in by a human,” Mastriano said in the radio interview.

Mastriano’s request for information is sweeping, according to a letter he sent to one of the counties, reviewed by POLITICO. It asks for all the ballots cast in the 2020 election and “all ballot production, processing, and tabulation equipment,” along with various “forensic images” of computer equipment and logs of databases.

It also asks for information on grants from the Center for Tech and Civic Life — a nonprofit that received an influx of cash from Facebook founder Mark Zuckerberg to provide money to cash-strapped local elections offices across the country. The CTCL grants have, in particular, been at the centerpiece of conspiracies about election fraud.

The letter threatened to subpoena the county if they did not comply, and Mastriano said he believed he had the votes on the committee to get subpoenas.

State Attorney General Josh Shapiro, a Democrat who is also considering a gubernatorial run, said his office would likely step in to defend counties that did not comply.

“Right now this information is being requested voluntarily but should subpoenas be issued, you can expect our office to do everything to protect the Commonwealth, its voters and the free, fair election that was held in Pennsylvania,” he said in a statement.

Other Democrats in the state pushed back against Mastriano’s proposed review as well, saying he didn’t have the authority to conduct it and was otherwise unfit to lead a review.

State Senate Democratic Leader Jay Costa and state Sen. Anthony Williams, Mastriano’s Democratic counterpart on the committee, wrote in a letter to Republican state Senate leaders that election oversight was out of the scope of the Intergovernmental Operations Committee, and said that Mastriano “is corrupting the committee process and politicizing it for the whims of former President Donald Trump.”

“We urge you to issue a cease and desist order for this member of the chamber before he does even more damage to the credibility of government institutions,” they wrote.

The expansive request could raise particular chain-of-custody issues for the local election officials. In Arizona, Maricopa County officials said they would get all new voting machines after turning over equipment to the state Senate’s reviewers over security concerns.

“This ‘audit’ could risk decertifying the counties’ voting machines, costing county taxpayers’ millions of dollars,” Shapiro said in his statement.

Trump himself has pushed for reviews in Pennsylvania and other states, attacking Republicans who did not back his calls. “Are they stupid, corrupt, or naive? What is going on?” he said in a statement last month. “What went on in Philadelphia and other areas of the State must be properly and legally exposed.”

In his announcement and interview, Mastriano continued to allude to unsubstantiated allegations of fraud in the election, citing changes made to the rules to ease pandemic-era burdens on voters. “It would defy logic to assume that an election with the kinds of drastic changes we saw in 2020 was run perfectly with zero errors or fraud,” he wrote.

Biden carried Pennsylvania by 81,000 votes — more than twice the margin that would have triggered an automatic recount.