We've known it was coming for some time, but on Tuesday the state of Indiana handed us an epic battle of the sexes. No romantic comedy, this, a la Doris Day and Rock Hudson.

Donald Trump, now the presumptive Republican nominee for president, engages in pillow talk with rivals only after he destroys them. Ted Cruz can now testify to that.

Nor will the plotline be anything classic in the way of “Lysistrada,” that ancient war-of-the-sexes tale in which wives withhold favors and so bring war-minded husbands to their dovish senses. Because Hillary Clinton, still the mathematically destined nominee of Democrats, is no pacifist. Already, she’s advertising her hawkish diplomatic credentials as she turns toward November.

Sure, policy will matter. Ideology and theology, too. But the scorched-earth presidential campaign headed our way will skew toward gender, because that is the strength and weakness of both Trump and Clinton.

On Tuesday, as Trump was dismantling Cruz in Indiana, a particularly interesting study surfaced that helped explain the billionaire’s bullet-proof standing among GOP voters and his ability to withstand a million-dollar onslaught from outside groups like Club for Growth.

Evolving Strategies, a Republican data and analytics firm that generally caters to Super PACs, tested four anti-Trump TV ads before 3,500 voters in the run-up to the Indiana primary. A significant number of women were persuaded to reject Trump. But Republican men were immune to the attack ads.

Adam Schaeffer, co-founder of Evolving Strategies, could explain female antipathy. “There are a lot of women who are really Republican voters who are really ambivalent about Trump. Under normal conditions, there’s no way they should be voting for a Democrat,” Schaeffer said. “Women are bothered more by the boorish statements, generally. It’s more personal.”

But Schaeffer couldn’t explain why white Republican men shut down when presented with any argument against Trump.

Exit polls of Indiana Republicans on Tuesday backed the study up, according to CNN. Trump held a 26-point edge over Cruz when it came to male supporters, but split the votes of women far more evenly, 47 to 41 percent. Which means that Cruz may have made a tactical error when he named former Hewlett Packard CEO Carly Fiorina as his running mate. A lack of support from GOP women isn't what did him in.

On the Democratic side, Clinton evenly split Indiana women with Bernie Sanders, who won the state. But she lost Democratic men to Sanders, 57 to 43 percent. Nationally, a recent George Washington University/Battleground poll found that views of Clinton among men are 33 percent favorable, 66 percent unfavorable. No wonder that Tuesday saw the former secretary of state not in Indiana, but in West Virginia, making amends with blue-collar workers. Most prominently men.

That same national poll showed Trump in an even deeper hole when it came to women. Seventy-eight percent of women under 45 had an unfavorable opinion of the man who is set to be the GOP nominee for president. Only two-thirds of women over 45 thought poorly of him.

The White House will go to the candidate who does the best job of undermining the gender advantage held by the other. On Wednesday, Georgia already had two instances of Republicans rejecting their gender-oriented destinies.

Julianne Thompson is — or was — co-chair of the national organization of women for Ted Cruz. She was caught flat-footed by her candidate’s decision to suspend his campaign Tuesday night. There was no advance warning. “It was a very big shock,” Thompson said.

She thought of doing a little grieving — and then decided against it. Yes, she has been put off by some of Trump’s more bombastic statements directed at women. But the thought of Clinton having one to three appointments to the U.S. Supreme Court changed her mind. She’s supporting Trump.

“It’s an easy choice for me,” Thompson said.

Then we have Erick Erickson, the WSB Radio host who famously thrust himself into the "never Trump" movement earlier this year. His group will have a conference call today — a "lifeboat" meeting, he termed it, to decide where he and other shipwrecked survivors might paddle to.

Erickson isn’t headed toward Clinton, but listed the three November options available: Quietly vote for Trump, find a third party to support, or write-in the name of an acceptable substitute. That last option is the one that will be exercised the most, he predicted.

Given his gender, I asked Erickson for his theory on that unanswered question we had a few paragraphs ago. Why are men so tightly glued to Donald Trump?

“I think Trump appeals to a particular segment of white men who feel like their culture is under assault. They’ve been beaten up and made the bad guy, and here comes Trump and he’s willing to fight back. He has been talking in a way that they talk, and in a way that they feel they can’t talk openly. And here comes a guy doing that,” Erickson said. “I understand the grievances, but I also think they’ve been conned.”

Before we ended our conversation, Erickson said that his Cruz contacts were still pressing him to become a delegate to the Republican National Convention in Cleveland. Even if the presidential contest is over, there are platform and rules fights to come. He’s considering it. Just in case.