The 2018 U.S. midterm elections are shaping up as a dramatic test not only of sentiment about the Trump administration, but also of prevailing gender roles in American society.

For much of the past year the so-called "Me Too" movement has drawn attention to sexual harassment and discrimination across broad segments of American society, ranging from motion pictures and the mass media to politics, and finally to Supreme Court appointments.

[Getty/Kyodo]

The narrow confirmation on Oct. 6 of Republican nominee Brett Kavanaugh to the Supreme Court, after a bitter debate concerning accusations of sexual assaults occurring over 30 years ago, only added fuel to a steady gender-linked transformation of American party politics that began in the early 1990s.

That transformation, involving an accelerating surge of younger women toward the Democratic Party, will likely show up dramatically in the November midterms, and could have major implications for America's future.

In the early days of female involvement in American politics, Republican women often played influential roles. The first woman elected to Congress, Jeanette Rankin in 1917, was a Republican who incidentally was also the only member of Congress to vote against American entry into World War I and World War II.

Margaret Chase Smith, also a Republican, became the first woman to be chosen in a regular election in 1949, and rose to chair the Senate Republican Conference, the third-ranking position in the Senate party leadership, before leaving the Senate in 1973. Nancy Kassebaum, who later married Howard Baker, similarly served with distinction as a Republican Senator from 1978-1997.

Things began to change sharply, however, in the early 1990s, driven by a landmark Supreme Court nomination controversy in many ways similar to the Kavanaugh debate just completed.

A Republican nominee, Clarence Thomas, was accused credibly of sexual harassment by a former staff assistant, Anita Hill, in 1991, yet he was subsequently confirmed. This stirred a firestorm of protest that led to a surge of female candidacies, and a sharp increase in the number of Democratic women in Congress.

The share of women in the Democratic Congressional caucus nearly doubled in the 1992 elections, from 7 to almost 14 percent, and has since more than doubled again, to 32 percent of the Democratic total at present. No comparable surge occurred among Republicans, where the share of female Congressional members rose much more modestly, from 5.5 percent in 1991 to 8.7 percent today.

To be sure, women secured a few major political advances before the so-called "Year of the Woman" in 1992, notably including Walter Mondale's selection of Geraldine Ferraro as the first female Vice Presidential candidate in 1984.

Particularly since the advent of the Clinton administration in 1993, however, Democratic women have recorded a series of firsts rarely equaled by the Republicans. Madeleine Albright became the first female Secretary of State in 1997. Nancy Pelosi, another Democrat, became the first female speaker of the House of Representatives in 2007. Barack Obama appointed eight women to his Cabinet, a record. And Hillary Clinton became the first female major-party candidate for President of the United States in 2016.

Rising opportunities for women in Democratic administrations, coupled with policy support on both gender-linked and broader human-security issues, and a backlash against Republican policies and candidates, has led to an accelerating shift to the left among American women generally, and especially among younger women.

According to the Pew Research Center, registered American female voters in 1994 identified with or leaned toward the Democratic Party by only a six-point 48-42 plurality. That margin had more than tripled, however, to a 56-37 margin in 2017.

Meanwhile, men were supporting Republicans in 2017 by a 48-44 margin, producing a gender gap of 11 percent. Male support for the Republicans has been quite consistent over the past two decades, and has actually increased since 2010, even as women have shifted decisively to the Democrats.

The shift to the Democrats has been especially pronounced among younger women, according to Pew, and has accelerated sharply since 2014. Support for the Democrats among so-called "millennial" women has risen quickly, from around 55 percent in 2014 to 70 percent three years later. It is especially strong among college-educated young women. Although data is incomplete, such support for the Democratic Party has likely risen even higher during 2018, reflecting the "Me Too" movement and backlash against the Kavanaugh nomination.

Meanwhile, all age-cohorts of American men, except the millennials, have generally stuck with the Republicans. Their support, however, has not risen enough to offset the sharp shift among women.

As a consequence, young women could well be the core of a "blue wave" of opposition to the Trump administration in Congressional races this fall, if they in fact do vote. And the "Me Too" and Kavanaugh controversies are giving them increased incentives to boost their historically weak turnout.

(Kent Calder)

Recent controversies seem to be deepening partisan sentiment on both the Left and the Right in American politics, likely strengthening the Democrats in the House of Representatives and the Republicans in the Senate.

This anomaly arises because all 435 members of the House are elected simultaneously, whereas only one third of the Senate is chosen. Elections in the House will thus reflect broad national trends, including the surge of female voters to the Democrats, as described above, which could be further intensified by the reality that there are 230 female House of Representatives general-election candidates this year (more than three quarters Democrats).

That will likely mean a substantial increase in the number of female Democrats in Congress (now 62, vs. 22 for Republicans), and most probably the election of the female Democratic leader Pelosi as the next Speaker of the House.

Due to accidents of geography, with only one third of the Senate being elected, and with most contested seats lying in states that strongly supported Donald Trump in 2016, the Senate will likely remain Republican by a narrow margin.

A Democratic House of Representatives, however, with a strong feminist tinge, will likely be a new reality of American politics. What that might mean, both for America and for the broader world, is a topic that needs much more serious consideration, as it would produce a very different political dynamic than we have known for the past two years.

(Kent E. Calder is director of the Reischauer Center for East Asian Studies at SAIS/Johns Hopkins University in Washington.)