In a political season filled with promises of revolution, something revolutionary happened: A woman has won a major party's presidential nomination.

That historic occurrence, overshadowed somewhat by everything else that has happened in an election year that has wildly defied expectations, will shape the general election clash to come. It sets up a November battle between presumptive Democratic nominee Hillary Clinton and presumptive Republican nominee Donald Trump that will tread heavily on issues of gender.

Those issues will dominate the election for at least two reasons. It will be the first time a woman has led a ticket in a presidential general election, and the two candidates already have been jousting over women and their roles.

In recent days, Trump questioned Clinton's very presence in the race.

"She doesn't even look presidential," he complained via Twitter as Clinton delivered a foreign policy address scathing in its criticism of the Republican.

The primary campaign has been loaded with such allusions to gender, and there's no reason to think that will change in the months before the general election.

The GOP primary contest "in many ways was all about who was man enough to be president of the United States," said Debbie Walsh, director of the Center for American Women and Politics at Rutgers University.

She cited Trump's complaints that former Florida Gov. Jeb Bush needed his mother's help to get elected, his criticism of Carly Fiorina's face as one that Americans wouldn't want on a president, and the dispute between Trump and Florida Sen. Marco Rubio over the size of Trump's hands and other body parts.

"It's all this masculinity," she said. "This is what presidential politics has always been about: Who is man enough, who is tough enough to be leader of the free world? The default image is always male."

Trump's "Make America Great Again" slogan harks back not only to a time before the civil rights of minorities had been secured, but also serves as a gender dog whistle, she said:

"Let's go back to a time when white men ran everything," it implies, Walsh said.

The official awarding of the Democratic nomination will occur during the summer convention, but media tabulations of delegate preferences showed Monday that Clinton had gained the prize. She is expected to claim it for herself Tuesday, when she is all but certain to increase her lead over Vermont Sen. Bernie Sanders in the popular vote, pledged delegates and superdelegates.

Her nomination would vault the country into the company of other nations that long ago elected women as leaders while high-level candidates here collided with what Clinton memorably called, at the end of her losing 2008 campaign, the nation's "highest, hardest glass ceiling."

Only two women have served on major party tickets -- Democrat Geraldine Ferraro in 1984 and Republican Sarah Palin in 2008. But both were picked for the vice presidential position, as opposed to winning the top spot outright, a distinct difference.

Now Clinton finds herself in a race with a surprising twist: In addition to being a referendum on a woman presidential nominee, it will also be a referendum on Donald Trump and his attitudes toward women.

Trump's treatment of women has been at the forefront of the presidential contest since the first Republican debate last summer. Fox anchor Megyn Kelly incurred Trump's wrath after she asked the candidate why he had described various women as "fat pigs, dogs, slobs and disgusting animals" and wondered how he would counter Clinton's general election assertion that he was part of a "war on women."

In April, Trump accused Clinton of being an affirmative action hire for the Democratic Party.

"The only card she has is the woman's card; she's got nothing else going," Trump said the night Clinton won Pennsylvania and three other states. "And frankly, if Hillary Clinton were a man, I don't think she'd get 5 percent of the vote."

His criticism prompted a line in Clinton's speeches that routinely draws her supporters into a shout-along.

"He accuses me of playing the woman's card," Clinton said Sunday night in Sacramento, before a community college gymnasium full of fans who burst into cheers at the line they knew was coming.

If standing up for equal pay, raising the minimum wage and family leave policies is playing the woman's card, she said, "then you know what? Deal me in!"

The fact that it was Trump who lit the fuse on the gender wars this year may influence the tenor of the fall campaign, according to those who have studied women candidates.

"He's the one making gender relevant and engaging in sexist talk, which opens the door to her response," said Jennifer Lawless, an American University professor who specializes in women in politics. "She doesn't have to defend herself from accusations that she's putting gender out there."

Overall, Lawless said, Clinton's achievement is "incredibly important."

"This is the first step to getting there," she said of the possibility of a woman in the Oval Office. "But she still has to win."

Women remain underrepresented in politics. According to the Center for American Women and Politics, they make up 20 percent of the Senate, 19 percent of the House, less than a quarter of state legislators and only 12 percent of governorships, despite being half of the population.

Apart from responding to Trump, Clinton has not had to overtly dwell on the historic reach of her candidacy; it's visible in every thread of her pantsuits. And it is deeply important to many of the women who have formed the heart of her campaign.

Some grow emotional at her campaign events when talking about the impact her nomination and election would have on them. For many, particularly those her age, Clinton is a stand-in for their own experiences with discrimination or, more benignly but no less hurtfully, being ignored or written off.

At a rally for women supporters in Manhattan the day before the April New York primary, actress Sally Sockwell, a year younger than Clinton's 68, gasped when asked how she would feel if Clinton achieved those historic firsts.

"I think it will just rip my heart out," she said. "It'll take my breath away."

That sentiment has driven the giant gap between the alliances of men and women in this year's general election contest. In an ABC/Washington Post poll last month, Trump led by 22 points among men and Clinton led by 14 among women. That 36-point gender gap is twice the average seen in presidential election exit polls since 1996, the pollsters said.