Why can't we upvote comments on nominations?
Normally a user can vote on a comment to indicate that they agree with the sentiment it contains; this saves them from having to post a similar comment. Using the same system during the nomination stage of an election would allow users to indicate that they share the concern previously raised by another user, or to add to the support shown by another user.
Added Later: Arthur Fischer's comment on Daniel Fischer's nomination appears to have been upvoted, but I still can't upvote any of the comments.