I wish I could hear the rest of the speech. Context is king, he could go on to say that the current welfare system does nothing to prop up those 47%.... or maybe not but still, it did end the speech rather conspicuously mid sentence. Either way, this video isn't good if you're a Romney supporter.
The fallacy here is that the 47% who don't pay federal income tax are the poorest 47%. This isn't true at all. Someome with a high salary and a lot of deductions may pay less than a guy making $30k who doesn't itemize. Besides most if the 47% still pay payroll tax. Its a false argument in every imaginable way.
Although there is plenty of that going around, it's not as if it were part of a thought, or a sentence from several. He made a pretty complete argument there. I don't see how he could wrap that up in a larger context where it would substantially change what he was saying. EDIT: Boston.com had some more excerpts. Here, I agree with Romney: “In a setting like this, a highly intellectual subject—discussion on a whole series of important topics typically doesn’t win elections,” he added.“We have a website that lays out white papers on a whole series of issues that I care about,” he said. “I have to tell you, I don’t think this will have a significant impact on my electability. I wish it did. I think our ads will have a much bigger impact. I think the debates will have a big impact.”
Could be the nail in the coffin? Then again, the majority of his supporters will likely applaud this.