On Monday, Mr. McCain appeared on “The View,” where his daughter, Meghan, is a host, and repeated his comments. He said that while he did not consider Mr. Trump a draft dodger, the system had been so broken that “certain Americans could evade their responsibilities.”

He did not deny that he had been talking about Mr. Trump, and was critical of the president for his past comments about prisoners of war.

But later, Mr. McCain insisted to reporters that he had not been talking about Mr. Trump, The Daily Beast reported.

“I was against that 40 years ago,” Mr. McCain said. “So for you people to say that I’m taking a shot at Trump over that, then you don’t know my record. It is unfair and unequal. The rich people didn’t serve and poor people did. It has nothing to do with President Trump.”