Pollsters found that reminding men about gender issues, specifically whether they earned more or less than their partner, led to a huge 24-point swing away from the female presidential candidate to the male alternative.
The matter did not seem to be divided along party lines – there was no such shift among participants asked to choose between Mr Trump and Democrat runner Bernie Sanders.
Instead, the survey suggests large numbers of men who perceive a threat to their masculinity will lurch away from the idea of a female president.
The study was conducted by the PublicMind team at Fairleigh Dickinson University in New Jersey, with married or cohabiting participants given a standard political survey with one extra question snuck in: Do you earn more, less or about the same as your partner?
“This was a simple experiment,” said Dan Cassino, who directed the research. “Half the people interviewed were posed with a question that prompted thoughts about gender and the other half were not.”
Only 15 per cent of men in the US earn less money than their spouse – but it was not the actual answer to the question that pollsters were interested in.
“The reason we asked the question was to push men to think about potential threats to their gender roles,” Cassino wrote in an article for the Harvard Business Review.
“Being the breadwinner has been a linchpin of US men’s masculinity for decades, so even the potential of making less than one’s spouse threatens accepted gender roles.”
Men who did not receive the gender question overwhelmingly supported Ms Clinton in a hypothetical match-up – by 49 per cent to 33 per cent.
But among men who did receive the gender question, Trump was supported by 50 per cent to 42 per cent.
The pollsters noted that women respondents invariably preferred Ms Clinton, whose campaign has specifically targeted female voters and has not been dogged by the same accusations of sexism as Mr Trump’s.
But women who were prompted to think about the gender pay gap were even more likely to vote Clinton, with a shift of around 10 points.
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