Note, an ad like that will, IMHO, radicalize public opinion on both sides. Whether it would help or hurt would depend on the mood and conventional wisdom of the country at the time that the ad is aired.
And here is an example of another possibility:
Tampa cable won't air ad criticizing Bush tax cut
TAMPA - (AP) -- A TV commercial critical of President Bush's tax plan won't air in Tampa after the city's major cable provider expressed concerns about the script.
The commercial was produced for MoveOn.org, an online political activist group, and was slated to air about 10 times a day this week on cable systems in 23 cities, said Lanicia Shaw, executive assistant for Zimmerman and Markman, a Santa Monica, Calif., advertising agency handling the commercial.
The ad is a reenactment of an event in Eugene, Ore., a month ago in which 50 parents lined up outside a clinic to sell their blood plasma to help pay a teacher's salary.
''George Bush's tax cuts for the rich have meant less money for education,'' the commercial contends.
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http://www.miami.com/mld/miamiherald/news/state/5862591.htm