Ford dismissed Whelan’s theory in a statement late Thursday: “I knew them both, and socialized with” the other classmate, Ford said, adding that she had once visited him in the hospital. “There is zero chance that I would confuse them.”

Republicans on Capitol Hill and White House officials immediately sought to distance themselves from Whelan’s claims and said they were not aware of his plans to identify the former classmate, now a middle school teacher, who could not be reached for comment and did not answer the door at his house Thursday night.

Whelan did not respond to requests for comment. He had told people around him that he had spent several days putting together the theory and thought it was more convincing than her story, according to two friends who had talked to him.