When either candidate reaches 270 electoral votes.
When the smirks on the main stream media whores become frowns or downright horror-filled. They’ll start making excuses or will state that results aren’t “conclusive” and that further mail-in ballots have yet to be tallied, blah, blah, blah...Watch for the media’s response - you’ll know if McCain has won by their response....
Kind of a “Duh!” dontcha think?