I'm sure I've said this before, but I don't believe that there is any way possible that Ness really hurts anyone's chances of getting in. I know that more goes into making a game and choosing the characters for it than "oh well look, teh mother seriz isnt ver popular wit people who arnt japan so lol i gess it only gets 1 rep :/". There's way more to it than that. Most of all, playability. It's not who knows the character (Mr.G&W) or how much of a spoiler said character is (Sheik), it's how well can a moveset be made for that character without making the character the best character evar or extremely lame.
I see all this stuff "Well if Ridley's in then that means Claus has more of a chance" but that's not the case. Think about Ridley. The only time he's ever been as big as Samus is in the first Metroid, and he couldn't be any bigger. Ever since he's been HUGE. You can't play with someone that big. Using Bowser to counter this statement holds no water, as Bowser isn't as large as Ridley. His wingspan alone seems to be the length of Final Destination. His confirmation would mean nothing more than Sakurai has gone mad or is a genious. Just because people suggested someone a lot on the character polls doesn't really mean anything, it's the sad truth.
But what isn't sad and still is the truth is that Claus is the one Mother character that could make people who have never played the series know that there is more to it than just casting magics. An almost fully physical fighter, with a history that almost kills the common perception of what Mother is all about, taking the story from one about the power of love and happiness and turning it into a real view of life, about how there is evil in everyone, and it can be brought out by anyone, about how death and sorrow can affect anyone, and about how even though it looks like you've completely turned to the side of evil, you can redeem yourself. Claus isn't in the same family of PSI users as Ness and Lucas. He only knows one PSI move. His thunder is generated by his sword, not by his mind. And all of that is what makes him more likely than any other Mother character, or really, any other character from any other obscure little series. And no amount of "proof" otherwise can really argue with that.