Do Political Ads Actually Work?

http://www.npr.org/blogs/itsallpolitics/2012/10/26/163652827/nine-states-near-unlimited-cash-a-flurry-of-ads

        Both democrats and republicians spend 1 billion on the ads that they run for the Presidential race. From April to October the ads have shown to be negative in a 7 to 1 ratio. In a report it says that even though there are alot of the policitical commericals people aren't compilteley tunning out of the commericals. As long as voters are still undecided the tv ads will continue to run.