In a series of interviews with donors, fundraisers and congressional officials, the depth of the concerns about what Trump’s latest attacks underscore become clear.

“Honestly? My worst fear. Call me stupid — I was one of the guys who figured he’d do the whole pivot thing,” said one donor, referring to an often-used strategy of moving more to the middle after securing the nomination.

The donor, who had been active for several candidates during the primary, said he was “ready to get in line” once Trump signed the joint-fundraising agreement last month with the RNC. The bold names associated with the joint agreement — people like businessman Woody Johnson — were enough of a sign, the donor said.

Now? “Not so much.”…

“The concern is — do we get to the point that all the money in the world doesn’t matter?” asked another donor, who said his whole goal this cycle was to protect House and Senate candidates. “We’re obviously not there right now, but stupid s— like this really makes you wonder.”