Depends on where he’s polling. I think he uses 2008 and 2010 turnout averages, and then leverages it against enthusiasm factors to get a proper sample figure.
Then yesterday, people were surprised that a couple people posted he had changed even that to D+6.
I'd love to know what he's using at the state level, but I'd settle for being sure about his national model.
I'm in a daily conversation lifting the spirits of many Romney people (to the truth, as far as I'm concerned), and making fun of my liberal friends, who will eat their words for every time in the past 3 months they have called me nuts, crazy, lying etc.