Photo: The Canadian Press

In this April 11, 1967, file photo, U.S. Sen. Robert F. Kennedy, D-N.Y., right, stands with Marian Wright Edelman, second from right, as they visit an unidentified woman in Greenville, Miss., during an anti-poverty investigation.

He was once called the most likely American in the 20th century to become president. But Robert F. Kennedy's bid to follow in his older brother's footsteps as commander in chief was cut short the same way John F. Kennedy's White House term was: by a man with a gun.

Fifty years later, Bobby Kennedy's life and transformation into a liberal hero is coming to Netflix in a new four-part documentary series available Friday. Through archival footage and interviews with friends and staffers, "Bobby Kennedy for President" takes an in-depth look at what drove him to seek public office, the events that shaped him and his legacy decades after his assassination.

"If we want to understand why Bobby Kennedy was so important to people, we have to understand all of it," said Dawn Porter, director and executive producer, also known for "Gideon's Army" and "Trapped."

The series opens with a broadcaster's prediction that "no American in this century has ever been so likely to be president as Robert Francis Kennedy." It takes viewers through Kennedy's combative time as attorney general, and his depression after his brother's death, entry into the 1968 presidential race and assassination 83 days later.

The documentary explores Kennedy's growth on issues like civil rights, through the guidance of black leaders like John Lewis, now a Democratic congressman. In documenting Kennedy's journey from a "cop-at-heart" lawyer to polished politician, it highlights experiences that affected him, like a trip to the Mississippi Delta that opened his eyes to rural hunger.