Why have the millions spent on TV ads against Donald Trump yet to slow down his presidential campaign? The answer may be men.

Evolving Strategies , a Republican data and analytics firm, recently tested the effectiveness of four anti-Trump TV ads ahead of Indiana’s primary on Tuesday. The results showed a deep split between the sexes.

Three of the four spots convinced a significant number of women — eight percent of those tested — to abandon the Republican front-runner.

But those ads didn’t work with men. The percentage of men who supported Trump didn’t waver even after viewing each of the four ads, the analysis found.



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That reaction explains why, to date, the blitz of televised negativity targeting Trump have yet to visibly slow his march toward the GOP’s presidential nomination, said Adam Schaeffer, who co-founded Evolving Strategies.