90 percent. That's how much of the National Republican Campaign Committee's ad budget will be spent on so-called "contrast" ads between now and election day, according to NRCC spokesman Ed Patru. The spokesman divulged the figure in an interview with Fox News. "Contrast" ads, of course, are negative ads. Patru boasted to Fox News that the NRCC's opposition researchers have been digging up dirt on Dem candidates for "over a year and a half." Just last week, the NRCC sank $7.8 million into 30 House races across the country -- almost all of it earmarked for negative campaigning.