If those numbers hold, they may spell disaster for Republicans in the upcoming midterm elections. Even more significant, they may signal that a monumental historical shift in partisan alignment is underway.

For more than 40 years, college-educated white women have formed a substantive bloc for the GOP, the key constituency in establishing the party’s hold on suburbs and exurbs across the country. Indeed, the modern conservative movement was built, in part, by the very type of women who may now be fleeing the Republican Party.

That movement owed much to Phyllis Schlafly, the Harvard-graduate lawyer who marshaled thousands of women against the Equal Rights Amendment (ERA) in the 1970s. A devout Catholic, Schlafly appealed to other religious women’s fears that the ERA would upend traditional gender roles and legalize the worst abominations, including gay marriage. She also tapped into a cultural sentiment among a certain set of white college-educated women that their class status and way of life was under attack—a sort of counterresponse to the argument feminists were making to a different set of women, who felt that their education was being wasted as homemakers.

Republicans built from Schlafly’s premise, assuring college-educated women in the 1980s that their economic program was best for their family. Ronald Reagan backed his pledge to shrink the federal government, slash business regulations, and cut taxes with the promise that doing so would put more money in Americans’ hands. Reagan boasted in 1984 that “millions of young families” had been “set free from unfair tax increases and crushing inflation” during his presidency.

White women thrilled to his message. It’s true that Reagan suffered from the “gender gap” in both of his presidential races, but that disparity depended on his poor support among women of color. He won a majority of white women in 1980 and again in 1984. The latter victory included nabbing 53 percent of white college-educated women.

Further reading: “I got into Yale” isn’t a moral defense.

The popularity of Reagan’s economic agenda among white college-educated women was coupled with their approval of his aggressive approach to the Soviet Union and his “tough on crime” stance. Convinced that Democrats were unsympathetic to their concerns, white suburban women viewed Reagan’s increase in military spending, his push for a nuclear-missile buildup, and his War on Drugs as essential to their family’s safety.

The belief that Republicans provided the strongest national security and would protect their family against Islamic terrorism bound white women more closely to the GOP after the events of 9/11. George W. Bush justified the war in Iraq, warrantless wiretapping, and enhanced interrogation as necessary for keeping Americans safe. White women agreed: Fifty-five percent voted for Bush’s reelection in 2004.