‘Genuine Love’ Between McCain, Hillary: HBO

John McCain’s “Genuine Love” for Hillary: HBO

(PEOPLE) In the sunset of John McCain’s 60-year service to the nation — first in the Navy and then in the United States Senate — filmmakers Peter, Teddy and George Kunhardt were granted extraordinary access to the senator and his family last summer as he started down the hardest road of his life: battling stage 4 brain cancer.

“He is the Republican lion of the senate,” Teddy Kunhardt tells PEOPLE before his almost two-hour documentary, John McCain: For Whom the Bell Tolls, debuts May 28 on HBO.

“[Hillary] genuinely loves this guy …”

The filmmakers found everyone from Barack Obama to George W. Bush to longtime friend Joe Biden extremely eager to make time to pay tribute to McCain on camera.

And while much has been made about the deep bonds between McCain, Lindsey Graham and Joe Lieberman, filmmakers were surprised to discover a real warmth between McCain and 2016 democratic presidential nominee Hillary Clinton.

“[Hillary] genuinely loves this guy and thinks the world of him,” says George Kunhardt. “They both lit up when we discussed them with each other. They both genuinely love each other. It was a very emotional and touching thing from our point of view.”

This was far from the only surprise in store for viewers of the film, which includes scenes of a relaxed and reflective McCain at his home in Sedona last summer — soon after his July diagnosis with glioblastoma, one of the deadliest forms of brain cancer.

In an interview on his porch, McCain revealed a shocker regarding his choice of Sarah Palin as his running mate for his 2008 presidential run.

“I should have said: ‘Look, Joe Lieberman is my best friend, we should take him,’ ” McCain says in the film. “But I was persuaded by my political advisers it would be harmful, and that was another mistake that I made.”

Read the full story at PEOPLE.

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