Looks like Smocke is digging himself a hole here. I don't see how he can possibly succeed at this point. Before this last week, he at least had people following him.. now they'll all turn against him. I'd be surprised if even Claire still follows him after that.
So it definitely looks like Jack is going to be "the one". We know Smocke can't kill him directly, so let's break it down:
Richard - Isn't stupid enough to kill Jack
Ben - Made that mistake already. Fool me once, shame on you. Fool me twice, shame on me.
Miles - Doesn't care enough. I don't think there's anything that Smocke can offer him.
Claire - Jack's her brother, and she knows it. She's hurt and confused, but she hasn't gone "dark side".
Kate - Not a chance in hell that she'd turn on Jack.
Sawyer - Ditto. Sure, he doesn't particularly like Jack, but he's not a fool.
Hurley - Wouldn't hurt a fly.
And.. that's about it.. everybody else is dead. Even if Frank's alive, he's Jack's friend.. he's not going to turn on him.
There's Widmore's people, I suppose, but none of them even know who Jack is. And Widmore himself obviously won't go against any of the candidates. (Speaking of which, how did he get the list?!? How does he know who the candidates are? Did Jacob make contact with him before he died?)
So basically you've got Smocke, who can't kill Jack directly. And there's no one left on the Island that's going to do it for him. So I'm curious how he plans to "finish what he started".
The only thing he might have up his sleeve is the ability to kill other people besides Jack. He can't touch Hurley or Sawyer, but Ben, Miles, Kate, and Claire are fair game. Richard.. I dunno.. it depends on how complete Jacob's protection is, I'm not entirely sure he
can be killed, despite what he attempted at the Black Rock.
It's getting interesting, though. 
I'm staying the hell away from spoilers. Even the Lost wiki has gone into lockdown mode until after the finale airs.
