In a presidential campaign packed with odd moments, Monday's Hillary Clinton rally in Kissimmee served up the most surreal one yet.
Seddique Mateen could be seen in the crowd steps away from Clinton as she paid tribute to the victims his son, Omar, killed in the worst mass shooting in modern U.S. history.
Throughout the rally, held about 20 miles from the massacre, Mateen waved a small American flag, took photos of Clinton with his phone and smiled.
And it was all caught on video.
Former vice presidential candidate Sarah Palin and conservative radio hosts Laura Ingraham and Sean Hannity were among those quick to jump on the Clinton campaign for allowing Mateen a prime seat just over the left shoulder of the Democratic presidential candidate.
"Unbelievable," Palin said on Twitter afterward.
Hannity, who is advocating for Donald Trump's election, led his nationally syndicated talk radio show with Mateen's appearance, questioning why the man who once expressed gratitude for the Afghan Taliban is endorsing Clinton.
"Why was he sitting behind Hillary last night?" Hannity said.
Veteran Florida campaign strategist Mac Stipanovich, a Republican who has declared himself part of the #NeverTrump effort, said Tuesday that someone in the Clinton campaign should have seen Mateen in the crowd and kept him away from the cameras.
"This was clearly a staff error and an embarrassing one," Stipanovich said. "Someone failed to ID him."
Mateen has spoken out against what his son Omar Mateen did on June 12, when he killed 49 people at the Pulse nightclub in Orlando and wounded another 53.
The Clinton campaign released a statement to reporters asserting that it did not specifically invite Seddique Mateen. But the campaign didn't respond to subsequent questions and offered no additional explanation as to why Mateen was at the rally or why he was seated so close to Clinton.
"The rally was a 3,000-person, open-door event for the public," a statement from the Clinton campaign said. "This individual wasn't invited as a guest and the campaign was unaware of his attendance until after the event."
The event was promoted on Clinton's presidential campaign website with an open call for all supporters to attend the rally at Osceola Heritage Park Exhibition Hall.
"Join us as we welcome Hillary Clinton to Kissimmee! Be there as she outlines her plan to make the biggest investment in good-paying jobs since World War II during her first 100 days in office," the website invite said.
Those wishing to attend needed to RSVP through the site, a step that ostensibly would have required Mateen to provide his name for admission later.
A spokeswoman refused to respond to additional questions about the vetting of the crowd, if Seddique Mateen RSVP'd through the website, or how he had such a premium seat.
One possible explanation for Mateen's seat? Optics. Campaigns often fill the backdrop with an audience the fits a key demographic, theme or look.
"They were probably going for a look — for diversity in the visual background — and (Mateen) fit the bill," Stipanovich said.
Mateen nearly went unnoticed at the rally. WPTV, the NBC affiliate in West Palm Beach, noticed the man in a red baseball cap just a few rows behind Clinton. Reporter Tory Dunnan eventually interviewed Mateen and asked him why he was at the rally.
"Hillary Clinton is good for United States versus Donald Trump, who has no solutions," Mateen told Dunnan.
When Dunnan asked Mateen if the Clinton campaign knew he was at the rally, he said, "It's a Democratic party, so everyone can join."
Contact Jeremy Wallace at firstname.lastname@example.org or (850)224-7263. Follow @jeremyswallace.