And, "IF" you could convince enough people to do so, then maybe you could help change the election's that will be close (which will be many, I'm sure). It's usually the "undecided" (?) that will vote "3rd" party in these situations anyhow.
It's a foregone conclusion that NY will go for Obama. So a vote for anyone else but him is a "wasted vote" if one believes the idea that voring for the losers is a waste. I don't, and will be voting for Barr. I like Nader, but Barr fits more of my ideals better.
The only wasted vote is the one not cast.
Even if it's to show up, and be counted as a none-of-these no-vote, it counts.