DENVER – Supporters of a new education tax proposal in Colorado are spending big to convince voters the income tax hike is a good idea.

The band of supporters is an odd mix, and includes both education reformers and unions which strongly oppose reforms, INewsNetwork.org reports.

New York City Mayor Michael Bloomberg’s foundation shelled out $1,050,000 this month to support Amendment 66, one day before Melinda Gates contributed $1 million to Colorado Commits to Kids, the group pushing the tax increase, according to the news site.

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The nation’s two largest teachers unions – the American Federation of Teachers and the National Education Association – have each donated $2 million. Walmart Heir Ben Walton, who has supported school choice options the unions hate, pitched in $500,000, according to media reports.

“So far, Colorado Commits to Kids has raised more than $10 million in support of Amendment 66, compared with about $41,000 raised by opponents,” INewsNetwork.org reports.

Those numbers are not promising for critics who believe the $1 billion annual tax increase is nothing more than a devious way to raise more money for the salaries and benefits of unionized teachers. Amendment 66 supporters contend the additional funding is needed to implement performance-based education reforms enacted by lawmakers in 2010, which would explain why Gates, Walton and Bloomberg support the proposal.

But the teachers unions fought long and hard against the 2010 reforms, so why would union officials be so eager to secure funding to implement them? Because the union hasn’t given up the fight against the reforms. If the amendment passes and the unions are able to repeal the reforms, the money will still flow in for teacher raises and benefit enhancements.

It will be too late to stop the gravy train from leaving the station.

The Denver Classroom Teachers Association and the Colorado Education Association plan to file a lawsuit to challenge the 2010 reforms, but sought and received a statute of limitations extension from the state board of education to delay the lawsuit until after the elections, according to media reports.

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What a clever strategy. We wonder what Bloomberg, Gates and Walton think of it.

“By pitching this tax increase as a means to carry out popular reforms, the teacher’s unions have an illusory advantage. But the very threat of this lawsuit shows their true position,” state school board Chairman Paul Lundeen told the Colorado Springs Gazette. “They seek to keep in our classrooms those few teachers who don’t belong there because those teachers are dues-paying members of the union. They want to pass the tax increase on the very classroom transformations they intend to stop in court.”