A liberal dark money group is giving the Koch brothers a taste of their own medicine by launching a multimillion dollar advertising campaign attacking the conservative Kochs’ “greed agenda.”

Patriot Majority began its campaign on Tuesday, with a $500,000 cable television ad buy for its spot, “Payback.”

The ad warns that the Koch brothers will spend $400 million to ensure President Obama’s defeat this November — and they will want something in return.

“What’s their payback?” the ad asks. “Politicians who will pass laws that benefit special interests but hurt the middle class. More tax cuts for the rich. Eliminate the minimum wage. Big cuts to our schools, but big subsidies for oil companies. Tax breaks for corporations that ship our jobs overseas.”

Patriot Majority, which has organizational ties to Senate Majority Leader Harry Reid, plans to continue its anti-Koch campaign through the fall.

“The Koch Brothers and their special interest friends have been pursuing their Greed Agenda for decades,” Patriot Majority President Craig Varoga said in a statement. “Just as Rome was not built in a day, it will take a lot more than a few months to stop the Greed Agenda. The effort that we’re beginning this week will eventually include all 50 states and will continue at the local, state and federal levels.”

Ironically, Patriot Majority is a 501(c)4 group. That means that, like the Koch brothers’ shadowy group Americans for Prosperity, Patriot Majority does not have to release the names of its donors.