Further, the party’s hard-line stances on immigration and health care, as well as its willingness to pass a tax bill that stung high-income districts, are as much the result of trying to assuage the far-right House Freedom Caucus as the president.

Yet there is a deep reluctance among the leaders to discuss what went wrong.

In an interview on the Saturday before the election, Representative Steve Stivers of Ohio, the head of the House Republican campaign arm, predicted his party would keep the majority. But, citing a handful of suburban incumbents, Mr. Stivers allowed that “if we wake up on Wednesday and all those have broken the other way, then it’s legitimate to say it was Trump.”

Reminded last week of those comments, the lawmaker would only say: “I’m not playing the blame game.”

He is hardly alone in averting difficult questions — or accountability.

Mr. McCarthy faced only a nominal challenge on his right flank in a leadership election that took place before the extent of the party’s defeats in California — they lost seven House seats — became clear. And Mr. Trump has ignored the House results.

The most the president has said took place the day after the election, when he used a news conference to belittle those who did not campaign with him and lost — an extraordinary tirade that few lawmakers condemned.

One who did was Representative Adam Kinzinger, Republican of Illinois. “That was disgusting,” he said, recalling how other presidents acknowledged defeat after their party lost the House. “I think back to Obama and Bush, both admitting it when they lost, accepting that with some grace.”

There has not been, Mr. Kinzinger said, “any party lookback or leadership lookback and it does worry some of us.”