Anyway,
PPP will post their results for the general election this week, so if indeed the race has tightened, PPP will be a good indicator!
Actually, I'm still incredibly wary of any national PPP poll. They were horrible in 2012 on that front.
http://www.realclearpolitics.com/epolls/2012/president/us/general_election_romney_vs_obama-1171.html#pollsPPP didn't seem to perform any national polls last time, and every other pollster appeared to get the national percentages wrong. 2012 was just a bad year for pollsters.