Most Offensive Campaign Ads Ever Produced
President George H.W. Bush.

President George H.W. Bush speaks at a presidential debate in St. Louis, four years after a controversial campaign ad helped catapult him to the presidency.

Brad Markel/Getty Images

What is the line between offensive and effective? In modern American politics, that line has been replaced with an equals sign. One of the most effective ways to get your name and your message into the national political conversation is to create a campaign ad that laughs (or spits, even) in the face of political correctness. Sure, you'll offend a few million people, but that's sort of the point.

The controversial "Willie Horton" attack ad against Michael Dukakis only aired once back in 1988, but it struck such a nerve that the news broadcasts replayed it again and again. With YouTube, an offensive ad can go viral overnight, turning a fringe local politician into a national political celebrity.

For your shock and awe, we have assembled a list of the five most offensive political ads ever conceived, starting with an unforgettable attack that aired on Michigan TV during Super Bowl 2012.