(CNN) – The liberal group Patriot Majority launched a cable television ad campaign Tuesday going after the Koch brothers, who are major supporters of conservative and libertarian causes.
Patriot Majority said it was initially spending $500,000 to air the ads, and expects to spend more than a million dollars by the end of 2012.
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"Billionaire oil tycoons Charles and David Koch and their special interest friends are $400 million to buy this year's elections and advance their agenda. What's their payback? Politicians who will pass laws that benefit special interests but hurt the middle class," a narrator in the minute-long spot says.
The ad claims the Koch brothers' donations to politicians are prompted by a desire for policies that would help them financially, including lowering tax rates for the wealthy and changing Medicare to allow private insurers to compete with the government-funded health program on an exchange.
The ad says those policies would hurt the middle class while lining wealthy people's pockets.
"Don't let the Kochs use their billions to buy this election," the narrator in the ad concludes.
The Koch brothers are high-profile figures in the Republican Party who support conservative and libertarian causes. Backers of the group Americans for Prosperity, the pair of industrialists are expected to spend tens – if not hundreds – of millions on Republican causes this year.
In July, the Kochs hosted a fund-raiser for Mitt Romney in Southampton, which drew multiple protests from Occupy Wall Street crowds.
Patriot Majority, founded in 2005 by a Democratic operative, has received a large chunk of its donations from labor unions, according to FactCheck.org. The American Federation of State, County and Municipal Employees gave the group $500,000 in 2010. The Service Employees International Union also donated to the group.
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