So far, the vast majority of House and Senate Republicans have shown no sign of taking the route Mr. Cohen and those few other Republicans followed and publicly challenging the conduct of a president of their own party. In contrast, Republicans today are taking an even harder line against pursuing further inquiry.
Senator Mitch McConnell of Kentucky, the majority leader, declared that it was “case closed” since the special counsel, Robert S. Mueller III, found no conspiracy between the Trump campaign and Russia to undermine the 2016 election.
“Two years of exhaustive investigation, and nothing to establish the fanciful conspiracy theory that Democratic politicians and TV talking heads had treated like a foregone conclusion,” Mr. McConnell said dismissively.
The Republican resistance to further scrutiny of the president was underscored by an internal backlash to the disclosure that the Republican-led Senate Intelligence Committee had subpoenaed Donald Trump Jr. to testify again before the panel, which is conducting its own investigation into Russian election interference.
“Senator McConnell said ‘case closed,’ and I think it is time for all Republican senators to get on board with that,” said Senator Rand Paul, Republican of Kentucky. He called the subpoena “overkill.”
“At this point, I see no reason other than partisanship to be dragging the president’s son down there,” he said.
Senator Marco Rubio, Republican of Florida, slammed House Democrats, saying they were manufacturing a conflict with Attorney General William P. Barr by moving to hold him in contempt for defying a subpoena to provide the full Mueller report and the underlying evidence. In 2012, however, Mr. Rubio had assailed Eric H. Holder Jr., President Barack Obama’s attorney general, for not cooperating with the House.