That's simply handled by saying that they should vote.
>one can legally be elected without the having the majority of the counter, valid, votes
How so? If you are referring to the President, did he not win the majority of the valid votes in the population allowed to vote? You could say there is an issue with only allowing a subset of the population to vote, but most people I've seen making such a claims still believe their own limits as for who can vote are valid and have not offered me a reason as to why one method is more valid than the other.