Ever hear of ‘the ends justifies the means’? Well, in this case, there is no justification for re-electing Obama because votes were cast for you, or any other third party wasted vote. The result would still mean Obama is re-elected, and that cannot be justified in God’s book.
Yeah. It's wrong.
And why not say, Let us do evil that good may come?... Their condemnation is just.
-- Romans 3:8