It remains undetermined whether three of Mr. Trump’s closest allies among House Republicans — Representatives Jim Jordan of Ohio, Doug Collins of Georgia and John Ratcliffe of Texas — will play a role. They had been expected to, at Mr. Trump’s urging, until the Senate majority leader, Mitch McConnell, advised against it, according to people close to the president.
Some close to Mr. Trump say that having Mr. Ratcliffe involved would be particularly helpful. The congressman helped lead the Republican defense in the House and has told people he is familiar with all the evidence that was presented.
Last week, Mr. Trump’s lawyers met at the White House with Stephen R. Castor, who served as the Republican counsel in the House impeachment hearings, according to people briefed on the discussions.
Mr. Castor was also at the White House before the final impeachment hearings, along with Republican members of the House, the people briefed on the discussions said. He did not meet privately with the president, but Mr. Trump wanted to thank him for his role in the hearings, they said.
Mr. Trump’s lawyers may also decide to expand the team, depending on how the trial unfolds.
The shaping of Mr. Trump’s defense team is playing out against a backdrop of contradicting signals from the president. On Sunday, Mr. Trump suggested that instead of holding a trial, the Senate should dismiss the House’s articles of impeachment that charge him with abuse of power and obstruction of Congress.
“Many believe that by the Senate giving credence to a trial based on the no evidence, no crime, read the transcripts, ‘no pressure’ Impeachment Hoax, rather than an outright dismissal, it gives the partisan Democrat Witch Hunt credibility that it otherwise does not have,” the president wrote on Twitter. “I agree!”
Hours earlier he seemed to endorse a trial, tweeting that Speaker Nancy Pelosi and Representative Adam B. Schiff, the California Democrat and Intelligence Committee chairman who led the impeachment inquiry, should be called as witnesses.