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.  

If anti-Trump Republicans want to prevail, Schaeffer said, they need a dramatic change in message — likely to something entirely new and as-of-yet untried.  

“When you’re looking at these ads, they’re not game changers,” said Schaeffer, the analytic firm’s director of research. “This is shifting margins only slightly overall.”  

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The failure of such ads to derail Trump’s campaign has been an enormous disappointment for Republicans who oppose the front-runner. They’d hoped that an on-air barrage would slow his momentum in the race to accumulate 1,237 delegates needed to clinch the GOP nomination. Trump is close to three quarters of the way to the mark.  

Early on in the primary, the other Republican presidential candidates focused most of their attacks on each other instead — a fact some strategists suggested fueled Trump’s rise to the top of the field.  

But the New York billionaire has thrived despite the best efforts of well-funded opponents. The free-market advocacy group Club for Growth and its political arm has spent about $11 million to oppose Trump. And the Our Principles PAC , a Super PAC formed to oppose Trump, has spent roughly $16 million.  

[Related: Trump Nails GOP Foreign Policy Impulses]
Trump swept last Tuesday’s five-state showdown in the Northeast, and polls suggest he’s en route to another victory in Indiana over rivals Ted Cruz and John Kasich .  

Schaeffer’s tests indicate that Trump mostly can thank men for that.  

He said he conducted randomized control trials from April 27-29 with 3,500 voters who were either registered with the GOP or leaning toward participating in the primary. They were asked in an online survey to watch one of four ads.  

The ads include one questioning Trump’s adherence to conservative orthodoxy , one repeating his past criticisms of women , one featuring attacks from Romney , and one highlighting the failed history of Trump University .  

Another group of voters, the control group, watched a commercial that had nothing to do with politics.  

Schaeffer picked the political ads to replicate the kind of attacks that have been leveled against Trump. They questioned Trump’s fealty to the GOP agenda, his character, trustworthiness, and temperament.  

Of the four ads, there was a clear loser: one titled “Know.” It highlighted Trump’s past breaks with the conservative agenda but failed to move any voters, including women. Fifty-four percent of men and 51 percent of women in Indiana still supported Trump after viewing the ad, which mirrored the totals in the control group.  

Three ads that questioned Trump’s character, however, had much greater resonance with women (these ads included the one that repeated his past criticisms of women, one that featured Romney, and one highlighting his history at Trump University). Trump’s support among women who viewed them dropped from 52 percent to 44 percent.  

“There are still women on the fence who are really ambivalent, and this seems to suggest that you can push them off the fence and back away from him fairly easily by raising concerns about his honesty and temperament,” Schaeffer said.  

But the ads failed to weaken Trump’s support among men.  

The study doesn’t explain why there is a discrepancy. Schaeffer said his best guess is that women care more about questions of character. And many of the other lines of attack against Trump already are well-known, which lessens their effectiveness.  

Asked what kind of ads would work, Schaeffer said anti-Trump Republicans might need to try a “Hail Mary. ”  

“Who knows,” he said. “But it’s not what is in this mix. It’s something that hasn’t been tried.”  

Katie Packer, who heads the Our Principles PAC, responded to the study with a short statement and a winky emoji .  

“I always thought that women were smarter than men,” she said.  

Contact Roarty at alexroarty@cqrollcall.com and follow him on Twitter @Alex_Roarty


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