Cross-post from another topic, but figured it'd probably be more fitting here:
I am going to laugh, btw, if Goku ever seriously gets into the game. He's no doubt received a ton of votes even if not being originally a game character makes him "ineligible". The company who makes Smash 4 actually does own his rights and he has, at this point, appeared in a ton of video games. It's in the realm of possibility that he is added as a second Namco rep.
I don't seriously expect it, and I'll seriously laugh if it happens. I just want to acknowledge that it is a possibility though, however remote.
I still hope Wonder Red gets in.
I'd like Hades too but I've sort of given up hope on him just because I see no one else talking about him.
My input on the other "popular" picks:
Bandana Dee - Dumb. Literally grasping at straws for another Kirby character...it'd be like putting in a Goomba.
King K Rool - Not the best character around, but sure why not.
Dixie Kong - I feel like a third Kong would be less interesting than K Rool, but I'd still welcome her.
Chibi Robo - I think some cool things could be done with the plug. A whip style moveset still hasn't been fully mined, despite Zero Suit Samus.
Isaac - Golden Sun is unfortunately a dead franchise but psynergy could lead to a really fantastic moveset. I'd love this choice. Hopefully he's more on the side of Robin though rather than Marth. We have a few too many straight swordsmen.
Krystal - A spear character would be an interesting addition...but no thanks. They're retconing her out of Star Fox with the new game anyways so it's pretty unlikely.
Paper Mario - Absolutely not. Paper Mario is cool and all but we already have multiple Marios. We don't need more.
Inklings - Almost seems like a no-brainer. Only reason they wouldn't happen is if they "save" them for the next Smash...but I don't see the real point in doing that. They're Nintendo's hot new IP and could have a really cool and unique moveset. I'd enjoy them as a choice also.
I think that's all the truly popular choices (from what I've seen) covered. If the ballot is legit (and the "votes" I've seen expressed on the Internet are accurate), the characters will probably be some of these. I guess Wonder Red, Inklings, and Isaac are my 3 top choices if I had to pick from these choices which appear most popular.