State Sen. Doug Mastriano, left, and Gov. Josh Shapiro (Mark Makela/Getty Images; Lev Raden/Getty Images)
Mastriano said that although he lost to Shapiro in 2022, the race saw the highest Republican turnout since 1962, and collected 29,000 ballot signatures.
Supporters claimed during the 2022 race that Mastriano would also have become the first GOP gubernatorial candidate to win without party endorsement intervention in the primary since Gov. Dick Thornburgh – who later became President Ronald Reagan’s attorney general.
"He further challenged Republican Party leadership, rejecting what he described as ‘backroom deals’ and ‘premature endorsements,’ and said future candidates must earn support directly from voters," the senator’s open letter went on, referencing his reservations about how the race was viewed by the establishment.
JOSH SHAPIRO CALLS KAMALA HARRIS BOOK CLAIMS ABOUT HIM 'UTTER BULL----' IN FIERY INTERVIEW RESPONSE
Mastriano also took aim at Shapiro, calling his governorship a "machine… corrupt and riddled with scandal, propped up by Hollywood elites and out-of-state billionaires who neither understand Pennsylvania nor respect its values."
"Josh Shapiro is not strong, not serious, and not fit to lead," Mastriano said, going on to suggest that former Vice President Kamala Harris "distanced herself" from him after vetting her potential running mates and instead choosing Minnesota Gov. Tim Walz.
Mastriano also condemned members of the media who "spent years trying to destroy [the Walk as Free People] movement while admitting they gave Shapiro a free pass."
JOSH SHAPIRO DEFENDS CLAIM THAT KAMALA HARRIS TRYING TO ‘COVER HER A—’ WITH CRITICAL BOOK EXCERPT
He added that while he will not seek higher office at this time, his work in the Senate will continue and proof of his movement’s veracity lies in its successful work helping elect Sen. David McCormick, R-Pa., and re-electing President Donald Trump.
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When reached for comment, a representative for the Shapiro campaign directed Fox News Digital to a statement from the Pennsylvania Democrats that said the commonwealth is now "stuck with" Garrity.
"Today, it became clear that Pennsylvania Republicans will be stuck with yet again another Republican extremist, Stacy Garrity, as their candidate for governor. Garrity is an election denier who has never stated Donald Trump lost the 2020 election and peddled the dangerous lies that led to the January 6th insurrection," the statement read in part, appearing to obliquely reference Mastriano's decision.
Charles Creitz is a reporter for Fox News Digital.
He joined Fox News in 2013 as a writer and production assistant.
Charles covers media, politics and culture for Fox News Digital.
Charles is a Pennsylvania native and graduated from Temple University with a B.A. in Broadcast Journalism. Story tips can be sent to charles.creitz@fox.com.
https://www.foxnews.com/politics/top-pa-republican-army-supporters-makes-major-campaign-announcement-shapiro-launches-re-elect