The Koch brothers’ political network spent hundreds of millions to win the White House and the Senate – and came up empty. So they did what any smart business executives would do: ordered up an audit.

But they’re not waiting for the final report for heads to roll.

Americans for Prosperity, the Kochs’ main political outlet, parted ways with its chief operating officer, most of its 100-plus employee field staff and several fundraisers. Generation Opportunity, a Koch-backed youth mobilization effort, recently replaced its president.

Charles and David Koch’s network also is withholding cash from some groups pending the full audit results, and it has postponed both of its signature donor conferences this year.

The pressure isn’t coming just from the inside. California regulators are issuing subpoenas and demanding phone and business records in an investigation that could reveal the secret donors funding some Koch-linked groups or even result in those donors becoming targets themselves. And David Koch has told friends he is weary of being pilloried by liberals and Democrats up to and including President Barack Obama as the personification of the corrupting influence of money in politics.

It’s not all gloom and doom in Koch World, but the brothers are at a potential turning […]