If you could save John F. Kennedy or Abraham Lincoln from being assassinated, who would it be and why?

Lincoln.  Kennedy ha already almost started World war three.  Given more time he would have.  

Honestly, JFK only for Jackie's sake.  She was such a good person and didn't deserve the life she got.

Abraham lincoln seem like a cool guy. I'll like to save him, but things change when bullets start flying. 

Lincoln. I don't like JFK's private life.

Tough call.

Lincoln staying alive and President means that Johnson's racist Reconstruction plan would not have taken place, and Southern rebellion and racism could have been far more firmly stamped down.

OTOH, JFK staying alive, and there's no question he would have won the 64 election, and the US doesn't go into Vietnam in any major way.

Lincoln he died trying to free slaves. I am a black guy so you get the idea. R.I.P. to both of them.

I wouldn’t interfere with the course of history. Butterfly effect.