Political pundits and pollsters, at times, have insisted this election is about immigration, democracy, and national strength during a time of global strife. But nothing—nothing—defines this election more than one thing: sex.

Across the board, polls prove men and women are split when it comes to choosing candidates. Harris is up by 14 points among women and Trump is up by 13 points with men, according to a New York Times/Siena survey of likely voters this month. A recent Pew Research poll found that Harris has an advantage over Trump by 9 points with women, while Trump is up 8 points with men. And an ABC/Ipsos poll from last month showed Harris up 13 points with women, while Trump was up 5 points with men.

But nowhere is this political divide clearer than among young voters.