NEW YORK – New York Gov. Andrew Cuomo is in the teachers union’s political crosshairs after he professed his support for charter schools, the union’s mortal enemy.

The United Federation of Teachers – New York City’s teachers union – and the statewide New York State United Teachers are spending millions in an effort to attack the governor over his support for public charter schools and his plan for a property tax freeze, Newsmax reports.

The two unions have sent a total of about $2.5 million to the New York Communities for Change and the Alliance for Quality Education. Both have accused Cuomo of “pay-to-play politics” for receiving campaign contributions from “Wall Street billionaires” supportive of charter schools, the news site reports.

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The issue on charters stems from the conflict between Cuomo and New York City Mayor Bill de Blasio, whom the unions worked tirelessly to elect to office.

De Blasio returned the favor by revoking co-location agreements between the city’s public schools and charter schools to share space in the same buildings. Teachers unions hate charter schools because they typically employ nonunionized teachers and school staff, which eats into the union’s potential dues revenue. The co-location agreements are a necessity for charter schools to operate in New York City’s sky-high real estate market.

At a rally of charter school proponents unhappy with de Blasio’s decision to revoke the co-locations, Cuomo said he’s “committed to ensuring charter schools have the financial capacity, the physical space, and the government support to thrive and grow.”

The governor has also opposed de Blasio’s plan to increase taxes on the city’s wealthier residents to fund pre-kindergarten programs. Cuomo has offered to fund pre-k through the state budget, without a tax increase.

De Blasio’s attack on charter schools is expected from a liberal who was elected with strong support from the teachers union, which says a lot about the mayor’s priorities.

Cuomo’s support of charter schools also says something about his character, political analysts have observed.

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“Opposing powerful teachers unions as a Democrat has long been viewed as committing political suicide, but in the case of Cuomo it has earned him kudos from some conservatives,” Newsmax reports. “Fox News’ Greta Van Susteren wrote, ‘He is obviously more interested in helping kids than in his political future.’”

“The public school teachers should be spending that $2.5 million they are using to attack Gov. Cuomo on making the public schools better, not in trying to tear down someone trying to help kids,” Van Susteren said, according to the news site.