Lincoln: "It was only with his death that Lincoln's popularity soared. Lincoln was slain on Good Friday, and pastors who had for four years criticized Lincoln from their pulpits rewrote their Easter Sunday sermons to remember him as an American Moses who brought his people out of slavery but was not allowed to cross over into the Promised Land"
Citing a 150 year old example is hardly a compelling case. And Lincoln had other things going for him. Like the fact that he was president. If Trump died I'm sure his opinion polls would go up too.
I stand by my point that if the only example you can find is 150 years old (and also has literally no similarities to Snowden - e.g. it wasn't even a government assassination or an enemy of the govt), you don't have much of a case.
From: http://www.civilwar.org/hallowed-ground-magazine/unpopular-m...