Lol at people's blood lust for Daryl. They're not going to kill him. They'd be stupid to do so. Especially to appease the small minority of haters.
Like someone said, he's the OT Han Solo, the Christopher Moltasanti to Rick 's Tony Soprano, meaning if and when they do decide to kill him off, it would be an episode or two before the series finale. Unless they decided to make movies afterward, then he'd stay alive for that.
Bottom line, there is no other character that has people threatening a boycott of the show or that sells merchandise like him. Especially his trademark crossbow and wings emblem. People really going to be going to buy a Morgan coffee mug with his bo staff on it? Lol
Rick, Michonne and Daryl are the big three, they're 99.9999% safe on that show, along with Carl.