04/24/2016 07:10 EDT | Updated 04/25/2016 12:14 EDT

This One Thought Makes Men More Likely To Support Donald Trump

“Merely asking the question” caused “enormous shifts” in men’s choice for president.

Men are more likely to support Hillary Clinton than Donald Trump for president of the United States — unless they’re prompted to think about gender, a recent study shows.

Decades of research show that men often react "in surprisingly strong ways" to what they think are threats to their masculinity, wrote the study’s author Dan Cassino in the Harvard Business Review last week. And the mere thought of a female president could end up costing Clinton eight per cent of the vote, the study says.

Republican presidential candidate Donald Trump speaks to guests during a campaign stop on April 4, 2016 in La Crosse, Wis. (Photo: Scott Olson/Getty Images)

Voters in New Jersey were asked who they would pick for commander-in-chief. However, half were first asked who the primary breadwinner is in their home. Those respondents chose Republican Trump over Democrat Clinton by an eight-point-margin.

Men who were not presented with that question first preferred Clinton over Trump by a 16-point margin.

The query had no effect on support for Bernie Sanders.

“Being the breadwinner has been a linchpin of U.S. men’s masculinity for decades, so even the potential of making less than one’s spouse threatens accepted gender roles,” Cassino wrote. “Merely asking the question” about income caused “enormous shifts” in men’s choice for president, he said.

The question had the opposite effect on female voters, according to the full study published by Fairleigh Dickinson University. About 36 per cent of women supported Trump when not asked the gender question. This fell to only 26 per cent when women were asked who earns the most in their home.

Only about 15 per cent of American men earn less than their spouses do, Cassino noted. And this is highly dependent on their stage of life — as men age, they become much more likely to make the same or more than their spouse.

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