John F. Kennedy's former top speechwriter says Barack Obama not only is a lot like Kennedy, but would make the best president.

Former Kennedy aide Ted Sorensen, 79 — the closest living aide to the slain president — also said he believed Hillary Clinton would likely lose to a Republican should she be nominated, according to the U.K. Telegraph.

"Both Kennedy and Obama have fantastically winning smiles and I might say both are very relaxed in front of an audience and on television. They don't shout into a microphone, they talk," Sorensen said.

Click here to read the full report in the Telegraph.

Sorensen said Sen. Obama, D-Ill., has "great judgment," adding: "Judgment is the single most important criterion for selecting a president." The Cuban Missile Crisis, for instance, tested Kennedy's judgment in 1962.

On Clinton, Sorensen said the New York Democratic senator was more calculating and formulaic than Obama, and predicted she'd lose.

"She's got everything going for her but a lot of people just don't like her," Sorensen concluded.

"The principles, the values Obama and Kennedy are enunciating are not five-point plans for new health care programmes, which is more Hillary's style."