The 2015 American Federation of Teachers annual report shows a left-wing political machine humming on all cylinders—with teachers buying the gas.

For the fiscal year ending June 30, the union reported $37.6 million in political activity and lobbying expenditures, a $12.7-million increase from the previous year.

Even more political spending was tucked away elsewhere in AFT’s annual U.S. Department of Labor filing, reported as “Contributions, Gifts and Grants,” “General Overhead,” or “Representational Activities.”

AFT paid union president Randi Weingarten, one of the nation’s most prominent “progressive” activists, a total of $497,118. The union reported only 2 percent of her time as political activity.

As in previous years, AFT funded a long list of left-wing political action committees, activist groups, and think-tanks.

In many states, teachers can be required to pay AFT to have a job. Even though mandatory union fees can legally be spent only on representation, the power to take money from non-members frees AFT to spend more member dues on politics.

AFT gave the Democratic Governors Association $1.5 million; gave Democratic super-PAC Patriot Majority $450,000; and gave the Democratic Legislative Campaign Committee $400,000 last year.

The union paid $410,000 to progressive coalition America Votes; $115,000 to MSNBC host Al Sharpton’s National Action Network; $90,000 to the environmentalist BlueGreen Alliance; and $15,000 to illegal immigrant advocacy group National Council of La Raza.

Millions of dollars of AFT payments to other political groups weren’t reported as political spending, including $300,000 in donations to Economic Policy Institute and $160,000 to National Public Pension Coalition.

A total of $323,889 in “advocacy organization” expenditures AFT reported as general overhead included a $60,000 payment to leftist donor network Democracy Alliance.

State Innovation Exchange, a pro-union attempt to copy the pro-business American Legislative Exchange Council, received $60,000 from AFT last year; AFT reported only $30,000 as a political expense.

A $50,000 AFT donation to Center for American Progress Action Fund was reported as a political expense, while a separate $50,000 donation to Center for American Progress wasn’t.

The union spent millions more on membership recruitment drives throughout the country, with $7.7 million in payments to “organizing projects” reported to the Department of Labor as representation costs.

Hundreds of thousands of teachers are stuck paying AFT, regardless of whether they agree with the union’s spending and activism. Friedrichs vs. California Teachers Association, a case before the Supreme Court, could change that within the next year.

If the Supreme Court sides with the plaintiffs in the Friedrichs case, it could end mandatory union fees for all public-sector workers.

AFT may come to regret “doubling down on a highly controversial political agenda,” Gary Beckner, chairman and president of the Association of American Educators, told Watchdog.

“Teachers have had enough and are searching for affordable, professional alternatives” like AAE, Beckner said. “Teachers deserve an organization that supports the modern educator—without the politics.”

AFT’s Washington, D.C., headquarters did not respond to a request for comment on the spending disclosed in the union’s 2015 annual report.

Originally published in Watchdog.org.