Frustration with Mr. Trump boiled over on Wednesday during a private conference call of House Republicans who had loyally stood by the president; many of them had joined a baseless lawsuit to try to overturn the results of the election. Representative Kevin McCarthy of California, the Republican leader, told members that he had spoken to the president and that he had not yet committed to a veto of the bill.

But Mr. McCarthy conceded, “This bill has been tainted,” according to one person on the call…

Some lawmakers on the call complained about the pork projects in the spending measure; others chimed in to challenge the characterization of the projects as pork, and one longtime House Republican vented generally about voter perceptions of the package after Mr. Trump’s scathing critique.

“I don’t know if we recover from this,” said Representative Virginia Foxx, Republican of North Carolina, according to three officials on the call. “We will have a hell of a time getting this out of people’s head.”