Men feel threatened by the idea of women making more money than they do, and according to new research, that can affect how they think and act politically.

Dan Cassino, a professor of political science at Fairleigh Dickinson University, conducted a poll to see how gender affects men’s outlook on the 2016 presidential election. The idea was pretty standard and straightforward: Ask men whether they preferred Hillary Clinton or Donald Trump in the general election.

But, half of the participants received a question about spousal income before the general election question and half of the participants received the question at the end of the poll. The question basically asked the men if they earned more, less or the same as their spouses.

Cassino said,

This was a simple experiment. Half the people interviewed were posed with a question that prompted thoughts about gender and the other half were not.

It’s hard to believe, but the spousal income question’s effect on male voters was actually huge.

Those men who were asked the spousal income question at the end of the survey preferred Clinton to Trump by 16 points, 49 to 33. Those men who received the spousal income question before the election question preferred Trump to Clinton by an 8-point margin, 50 to 42.

Interestingly, the spousal income question did not affect the outcome of a matchup between Bernie Sanders and Donald Trump, which seems to indicate the swing happened because of Clinton’s gender, not her status as a Democrat.

Come on, men! Are we all so threatened by the idea of women earning more than we do? I mean, a 24-point change is too much, guys. We all need to work on our reflexes a little more if we’re willing to vote for one candidate simply out of fear for our masculine identities.