Americans for Prosperity spokesman Christopher Neefus says the ad launched Tuesday will air for three weeks in all major markets.
Titled "It's Working Wisconsin," the ad features people talking about Walker's proposal passed in 2011 that effectively ended collective bargaining for most public workers and required them to pay more for pension and health benefits.
Walker is being challenged by Democrat Mary Burke. Her campaign spokesman Joe Zepecki says contrary to the ad's claims, Wisconsin families are struggling and Walker's policies aren't working.
A Marquette University poll last week showed voters were evenly divided between Burke and Walker.
Watch the ad: