Ashley May

USA TODAY

Among speculation that Democratic presidential candidate Hillary Clinton's health is failing, there's another theory gaining traction online: she might have a body double.

The only "evidence" of this theory is photographs taken Sept. 11, when Clinton ducked out of a 9/11 anniversary ceremony in New York because she felt "overheated" and is battling pneumonia.

Some say the differences lie in the details: cheekbones, smooth versus wrinkled skin and body composition.

Many said it was strange Clinton wasn't surrounded by security for part of the day Sept. 11. She took her time walking along a sidewalk, telling spectators she was feeling "great" and stopped to pose for a photo with a young girl.

Famous Clinton impersonator Teresa Barnwell first played along, tweeting she might have been in New York that day. She was actually on the West Coast, preparing for a Spike TV network show. She had been in New York just a few weeks ago and a friend took her past Chelsea Clinton's building, where they took photos.

"As I was sitting in my dressing room, I posted [a photo] to have a little fun," Barnwell said, adding that she had never shared the New York photo previously. "I had already posted that I was in L.A. before that, so I was just joking with people."

Barnwell later said she was in Los Angeles during the time of the photos, telling people to “calm down.”

Christopher Weddle The (Palm Springs, Calif.) Desert Sun contributed to this report.

Follow Ashley May on Twitter: @AshleyMayTweets