WaPo:
Establishment Republicans and their big-money allies are rushing to build a multistate defense system to protect Senate and House candidates, fearing that the party could lose its hold on Congress if Donald Trump is at the top of the ticket in November.
The anxiety about Trump’s potential spillover effect on down-ballot races was underscored Wednesday when House Speaker Paul D. Ryan of Wisconsin lamented the “disheartened” state of the campaign and criticized the “identity politics” on display in the increasingly toxic race for the GOP presidential nomination.
The efforts are being driven by major players such as the Koch brothers’ political network, which has already begun laying groundwork in Colorado, Ohio and Pennsylvania, along with the Crossroads organizations and the U.S. Chamber of Commerce.
The behemoth Koch operation — which aims to spend almost $900 million before the November elections — is now considering abandoning Trump as a nominee and focusing its resources on behalf of GOP congressional candidates.