A political organization funded by the billionaire Koch brothers will ramp up its presence in Tennessee K-12 education, the Tennessean reports.

The Koch brothers, whose corporation Koch Industries is the second-largest privately held company in the nation, have made a reputation of reshaping the American political landscape according to their free-market principles by funding an empire of political-action organizations that support political campaigns of like-minded politicians. Recently, organizations funded by the brothers have focused on education. In Tennessee, their primary focus is getting rid of the Common Core State Standards.

Joey Garrison of the Tennessean reports that a spokesperson for Americans for Prosperity, one of the brothers’ political action groups, said that he’s embolden by school board wins the foundation helped fund in Williamson County:

“The Tennessee branch of Americans for Prosperity . . . claims it spent $500,000 over the last six weeks targeted at ‘bringing the issues with Common Core to light’ in Tennessee. ‘And this is just the beginning,’  the group’s state director, Andrew Ogles, said in prepared statement Wednesday.”

Americans for Prosperity is a 501 (c)(4) organization, meaning that it operates to promote of “social welfare,” and cannot donate money to individual candidates. So the group, which set up a branch in Nashville last year, campaigned against the Common Core, rather than for specific candidates. The Tennessean reports:

“Efforts included mail pieces that mentioned Beth Burgos, a family doctor who defeated incumbent Eric Welch, and urged people to thank her for efforts to ‘stop Obama’s radical agenda.'”

Even the candidates themselves found the help mysterious. “We didn’t know anything about it,” Burgos told the Tennessean. “I caught some flack from that. Other people liked it. But I knew nothing about it. It was crazy when it hit my mailbox, too.”