He broke the news to supporters in an email Thursday.
“I have done a lot of deep thinking, and I actually believe I could win the primary. However, I’m not personally convinced that I help the ticket in the long run- in the General Election, and that’s what this should be about,” he said.
“Therefore, I will not be a candidate for office this year.”
Crossey, 63, first floated his name at a state committee meeting in June. A former member of Allegheny County Council, he resides in Mt. Lebanon.
PSEA is the state’s largest teacher’s union and has significant sway in Democratic politics.
Several Democrats have declared bids for LG, including Harrisburg City official Brenda Alton, Former Congressman Mark Critz, Harrisburg City Councilman Brad Koplinski, Bradford County Commissioner Mark Smith and State Senator Mike Stack (D-Phila).
Several more are considering it, including state Sens. Larry Farnese (D-Phila) and John Wozniak (D-Cambria) as well as State Reps. Margo Davidson (D-Delaware), John Galloway (D-Bucks) and Brandon Neuman (D-Washington).