But he was also known for establishing constructive relationships with people with whom he clashed ideologically.

“Mark Meadows has a live intellect and emotional life,” said Representative Jamie Raskin, Democrat of Maryland, who had a good relationship with Mr. Meadows when he served as a congressman. “Again, I consider many of his ideological commitments just indigestible, but we try to find the humanity in our colleagues and he is someone with a mind and a heart, that’s just undeniable.”

But neither quality is necessarily an asset in the Trump White House, where the president likes to project strength at all moments.

A former businessman and real estate developer, Mr. Meadows bonded with Mr. Trump early in the administration and helped push his agenda increasingly to the right. When Mr. Meadows announced that he would step down from Congress, it immediately prompted speculation that he would join the White House.

He was brought in by Mr. Trump as part of a staff shake-up just as the administration was overwhelmed by the fast spread of the coronavirus in the United States and struggling with equipment and testing shortages.

In the middle of the crisis, Mr. Meadows is trying to reorganize the White House staff. People close to him insisted Mr. Meadows’s nature was not to fire people willy-nilly, but they said that was what he was doing nevertheless.

He is also talking about other changes, two people familiar with the planning said, such as reorganizing the speech-writing team — currently a stand-alone office led by Stephen Miller — under the umbrella of the communications department. That discussion has met with some resistance, although one person with knowledge of the changes under consideration said the idea was to synthesize different departments that do not always work in tandem.