A new ad campaign is hitting Donald Trump where it hurts—his manhood.

The series of four videos was concocted by Bob Gardner, a longtime Republican adman, to “unsell” Trump’s presumptive GOP presidential nomination, according to Politico.

One of the spots is a 30-second ad featuring a young woman doing yoga and talking candidly about Trump and his “small hands.”

“I like macho guys — take-charge, competent guys — guys with big hands. Real men,’’ she tells the camera. “But real men don’t go around dissing Muslims and Mexicans. … They’re not bullies. And real men don’t talk about their size. … Guys like Donald Trump who brag about how big they are? You can’t be president, Donny boy. You just don’t measure up.”

Gardner told Politico that the ads were originally intended to air in California—which was supposed to be the site of a final GOP showdown before Texas Sen. Ted Cruz dropped out of the race—but he decided to put them online for all to see on Youtube.

Even Gardner isn’t sure if the ads will have any effect on stopping Trump from becoming the Republican nominee at the July convention.

“This year has been so unpredictable that I hate to hazard a guess,’’ he told Politico. “I and most others have been wrong at every turn.”

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