Why the powerful Koch network’s Nikki Haley endorsement matters

Americans for Prosperity Action, a super PAC that's part of the powerful Koch political network, announced Tuesday it's backing Nikki Haley for president. It's big news: The network billionaire brothers Charles and David Koch founded had raised more than $70 million for political spending by this summer — after sitting out the last two presidential contests. "Haley is in the best position to defeat Donald Trump in the primaries," AFP senior adviser Emily Seidel argued in the endorsement memo. And, Seidel continued, "our internal polling consistently shows that Nikki Haley is by far the strongest candidate Republicans could put up…