During moderator elections, a nomination includes certain statistics about the candidate. This information used to include the number of helpful flags, but this was removed because of concerns that comment flags were unbalancing this -- what we really care about, as I recall the discussion, is post flags, but we only had the one number. So "800 helpful flags (but 760 of them were comments, which we aren't telling you)" was deemed harmful and removed.
Since that decision, flag reporting has changed and flags on individual user pages are now broken down into categories:
Could we expose that information somehow?
We could do this on the "election details" page (linked from the election page), like this (this is number helpful / number cast):
An alternative would be to report "flags" (not "post flags"), with the two numbers being posts and comments. This would lose the signal about flags that weren't accepted. I don't know which is more important.
I think including this data in the election details is fine and it doesn't also need to be on the candidate card. I mean, meta participation isn't on the candidate card either (except obliquely through badge counts), and that's pretty important.