I also understand that he mixed several ideas. The conservative complaint that about 47% of people don't pay income taxes got mixed with the reality that about 47% of the electorate would never vote for him. The two groups aren't the same although there would be some overlap in a Venn diagram. The third idea thrown in was the Ayn Randian adolescent fantasy of the producers and the moochers which is about as accurate as the philosophical fantasies that divide the world into orcs and hobbits.
The reason why 47% creates a majority is not the pure math, but the concept that the 47% statement has now created a clear preference for President Obama that may well last through the election. In spite of Governor Romney's confusion in mixing three different ideas at the fundraiser, people get this instinctively. That's why this Obama ad is so powerful, and effective:
The "47%" will be the phrase most remembered in the history of the 2012 campaign just as the made-up, but Sarah-inspired phrase "I can see Russia from my house!" defined the 2008 McCain-Palin campaign. Even if Governor Romney manages somehow to win, it will be how he overcame such a devastating self-inflicted blow to his campaign.
Maybe Romney can make a come-back or the President can actually flub something big-time. I know a lot of angry people think Obama's been doing that for nearly four years now. But you know what? That angry crowd doesn't even come close to 47% of the 2012 electorate. They are a distinct minority even if a very loud one (besides the fact that many of them likely don't pay any income tax and certainly receive the benefits of our government of, by, and for us - as we all do in one form or another). I think that now Governor Romney's 47% statement has woken up the sleeping giant of the electorate, the voice of the people will prevail. (Well, it certainly will one way or another!)
|Early Voting has begun in Iowa|
|From Nate Silver's FiveThirtyEight 9/28/2012|
("Now-cast" on 538 means "if the election were held today")