For more on the teachers' unions enormous political giving (and resulting power), see this brilliant expose in Education Next by Mike Antonucci:

The largest political campaign spender in America is not a megacorporation, such as Wal-Mart, Microsoft, or ExxonMobil. It isn't an industry association, like the American Bankers Association or the National Association of Realtors. It's not even a labor federation, like the AFL-CIO. If you combine the campaign spending of all those entities it does not match the amount spent by the National Education Association, the public-sector labor union that represents some 2.3 million K–12 public school teachers and nearly a million education support workers (bus drivers, custodians, food service employees), retirees, and college student members. NEA members alone make up more than half of union members working for local governments, by far the most unionized segment of the U.S. economy.

The Center for Responsive Politics and the National Institute on Money in State Politics joined forces last year to produce the first comprehensive database of political campaign spending at both the state and national levels. The results should open the eyes of policymakers and educators alike, as well as those involved in the wider world of domestic politics. In the 2007–08 election cycle, total spending on state and federal campaigns, political parties, and ballot measures exceeded $5.8 billion. The first-place NEA spent more than $56.3 million, $12.5 million ahead of the second-place group. That's not all. The American Federation of Teachers (AFT), the smaller of the two national professional education unions, ranked 25th in campaign spending, with almost $12 million, while NEA/AFT collaborative campaigns spent an additional $3.4 million, enough to earn the rank of 123rd. All told, the two national teachers unions distributed $71.7 million on candidate and issue campaigns from California to Florida, Massachusetts to South Dakota. Millions more went to policy research to support the unions' agenda.

The teachers unions outspent their union peers by a large margin. The next highest-spending public sector union is ranked at number 5: the Service Employees International Union (SEIU) contributed some $35 million. The AFL-CIO's largest member union, the American Federation of State, County and Municipal Employees (AFSCME), at less than half the size of NEA, spent about $21 million and ranked 11th.

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