What if Gollum had lived?

[Tuor in Gondolin]

And yet but for Sam's clumsiness and protectiveness towards Frodo Gollum might have repented.

Letters #96

...For myself, I was prob. most moved by Sam's disquisition on the seamless web of story,
and by the scene when Frodo goes to sleep on his breast, and the tragedy of Gollum who at that moment
came within a hair of repentence-but for one rough word from Sam.