During a closed-door gathering of major donors in Southern California on Monday, the political operation spearheaded by the Koch brothers unveiled a significant new weapon in its rapidly expanding arsenal — a super PAC called Freedom Partners Action Fund.

The new group aims to spend more than $15 million in the 2014 midterm campaigns — part of a much larger spending effort expected to total $290 million, sources told POLITICO.,

It’s an evolution for billionaire industrialists Charles and David Koch. The vast network of political nonprofit groups they helped build has mostly funneled its unprecedented political spending into issue-based campaigns that usually slam Democrats for supporting big government but seldom explicitly ask voters to support GOP candidates.

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That’s expected to change under Freedom Partners Action Fund, according to Marc Short, president of Freedom Partners Chamber of Commerce, an increasingly powerful force in the Koch network that will operate in association with the new super PAC.

“The Freedom Partners Action Fund will support candidates who share our vision of free markets and a free society and oppose candidates who support intrusive government policies that push the American Dream out of reach for the American people,” Short told POLITICO after a presentation to donors at the St. Regis Monarch Beach resort in Dana Point, California.

The gathering is the latest in a series of twice-annual so-called seminars that the Kochs started holding in 2003 to raise cash from wealthy donors after treating them to a series of slickly produced presentations from handpicked politicians, conservative media stars and operatives from Koch-backed groups.

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Freedom Partners, which was created in 2011, now organizes and hosts the seminars. The theme of the St. Regis seminar — “American Courage; Our commitment to a free society” — was printed on massive posters evoking an idyllic turn-of-the-century immigration motif. The posters, which depicted an immigrant family gazing in awe at the Statue of Liberty in the distance, were displayed throughout the St. Regis. A photo of one was provided upon request to POLITICO by Freedom Partners spokesman James Davis, who explained that the purpose of the seminar was “continued discussions about advancing a free society with the theme of American Courage.”

Among the dignitaries who was scheduled to address the crowd was Sen. Marco Rubio (R-Fla.), whose office declined to comment on his appearance. It was initially reported by the Daily Beast, which also first reported the $290 million overall spending goal.

Democrats are sure to seize on the new Freedom Partners super PAC as yet more fodder in their mounting campaign to caricature the brothers as evil puppeteers manipulating Republicans. The Democratic Congressional Campaign Committee sent a fundraising missive Sunday declaring the Daily Beast’s report “AWFUL NEWS” and pleading “if we can’t start closing this gap TODAY, the Koch brothers WILL buy the election for John Boehner and the GOP.”

A spokesman for Koch Industries, the Koch brothers’ privately held industrial conglomerate, referred all questions to Freedom Partners. A Koch Industries website entry posted before Freedom Partners took over responsibility for the seminars describes them as an opportunity for “America’s greatest philanthropists and most successful business leaders” to “discuss solutions to our most pressing issues and strategies to promote policies that will help grow our economy, foster free enterprise and create American jobs.”

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