In North Carolina, GOP Senate nominee Thom Tillis had built leads of up to 14 percentage points among men in recent polls. Republicans who have won male voters by that margin have only lost two Senate races in the past 10 years, according to exit polls. It's equal to the margin Republicans posted nationwide during their electoral sweep in 2010.

But Tillis has consistently trailed in recent surveys, because Democratic Sen. Kay Hagan—whose campaign, like her party's efforts in Colorado and elsewhere across the country, has focused relentlessly on issues of greater importance to women—has run up the score even higher among female voters.

The "gender gap"—the difference between Republicans' usual margin of victory among men and Democrats' usual margin of victory among women—is nothing new. It has been evident for years in almost every election up and down the ballot. But a National Journal analysis of public polls, and interviews with strategists from both parties, suggests that the gap has ballooned to historic proportions across 2014's battleground states. Democrats are running campaigns designed to press an advantage among women that is helping the party compete in a number of races despite an unfriendly political climate and steep GOP advantages among men. Meanwhile, Republicans are searching for issues to combat the trend with female voters.

"I think the gender gaps are growing compared to past election cycles," said Matt Canter, the Democratic Senatorial Campaign Committee's deputy executive director. "We'll see how that turns out, but that's certainly what the public and internal polling shows, in every race across the board."

It's a trend several Republicans privately admitted they are watching nervously, though some point out that one end of the growing gap isn't bad news for the GOP. "I haven't seen gender gaps like this in any race until this year, and we're seeing them all over the place," said Nicole McCleskey, a New Mexico-based Republican pollster for Public Opinion Strategies. "Typically people say we're in bad shape with women, but it's also that Democrats are not doing well with men. That's why the gap is exploding like it is."

In Senate and governor's races since 2004, the average gender gap has been 13 points, according to a review of exit polls from the past decade, and just seven races (out of more than 200 measured in that time) have had gender gaps of more than 30 points. (The 2010 Colorado Senate race, in which Republicans carried male voters by 14 points but lost among women by 17 points for a 31-point gender gap, is one rare example.)

Since August, though, independent live-caller polls of Senate and gubernatorial battlegrounds have had an average gender gap of more than 20 points, and the gaps have topped 30 points in multiple polls of three races: the North Carolina and Iowa Senate contests and the Massachusetts gubernatorial election. There are only three battlegrounds where Democrats have trailed among women in a Senate or gubernatorial contest, and only another three where Republicans have trailed among men in any independent live-caller poll.

GRAPHIC: Compared to recent elections, this year's polls show larger gender gaps.

Even as Senate polls in New Hampshire have tightened, a wide gulf between women's support for incumbent Democrat Jeanne Shaheen and male support for Republican Scott Brown has remained. Democrats in Colorado have made the Senate campaign there all about abortion and birth-control access, driving a larger-than-average wedge between Republican Rep. Cory Gardner and women voters even as he does well among men in polls. That issue, along with equal pay, the Violence Against Women Act, and several others, have come to the fore in 2014 as the Democratic Party seeks to take advantage of numerous Republican lapses with women voters over the past few years, in rhetoric and policy.

"There's an underlying, structural gender gap, with women more likely to identify with the Democratic Party and men more likely to identify with the Republican Party," said Democratic pollster Mark Mellman. "But on top of that, the forces of this campaign and the way Republicans are seen as treating women "... that's another layer" building on top of the existing trend.

The epicenter of this polling trend may be in North Carolina. While men have given Tillis major support, women voters have avoided him as much as any major GOP Senate candidate in the country, according to public surveys, which have consistently produced some of the largest gender gaps of 2014. Meanwhile, the campaign has hinged on issues of particular importance to women voters—especially education, an issue polling has long shown matters more to them than men. Democratic TV advertising in the state, from Hagan's own campaign to allied outside groups, has focused on education cuts passed through Tillis's state House.

"Women have never played a bigger role in elections," said EMILY's List President Stephanie Schriock, whose group aired an anti-Tillis ad that featured a pregnant schoolteacher buying classroom supplies out-of-pocket after budget cuts. "In races across the country—and especially in North Carolina—the focus is on women's issues, women candidates, and women voters."

Colorado is another major example. Polls there have shown a wider gender gap between Democratic Sen. Mark Udall and Gardner than between the Democratic and Republican candidates for governor, who have focused on other issues while Udall has prosecuted an abortion- and contraception-based case against his GOP opponent. The gap is evident in a number of governor's races, though: In Michigan, for example, GOP Gov. Rick Snyder has been running even with Democrat Mark Schauer in several recent polls, despite a double-digit advantage among men, thanks to Schauer's strength among women.

The large gender gaps in current polls don't necessarily forecast gaps as huge in the actual vote in November. Breaking public polls down into smaller samples means that those numbers become less reliable, and there has been a lot of variation even within the same states. For example, the gender gaps in six Iowa polls taken over the last month have ranged from 6 points to 38 points in the most recent poll, from The Des Moines Register. And some national polls, including the most recent survey from NBC and The Wall Street Journal, have shown Democrats losing support among women on the generic ballot, when respondents are asked if they'd rather have Democrats or Republicans in control of Congress next year.

Plus, even as Democrats are putting in strong performances overall among women, there's as much of a marital gap as a gender gap. Republicans often lead among married women but get trounced among single women—a key demographic that Democrats are working to turn out.

"The media narrative about the 'gender gap' is wrong, or at a minimum mischaracterized," said National Republican Senatorial Committee spokeswoman Brook Hougesen. "In battleground states, Republican candidates are winning a majority of white women, are preferred by married women by double digits, and are statistically tied among single white women. The fact is that Democrats have a far bigger problem with male voters than Republicans do with females."

But for the moment, women are keeping the GOP from turning a wave among men into an overall electoral rout.

"Clearly there's a gender gap, and clearly Democrats are doing all they can to exploit it," said Katie Packer Gage, a Republican strategist whose firm, Burning Glass Consulting, was created to help Republican groups communicate more effectively with women voters. But Gage noted several reasons why the poll numbers might be soft.

"A lot of these numbers may be driven by younger women, the most difficult group of voters to get to the polls," Gage continued. "Another thing Democrats are going to have a real challenge with is national security coming to the forefront," which Gage said could help her party make further inroads with women before November.

In Senate Republicans' latest TV ad in Colorado, a female narrator accuses Democratic Sen. Mark Udall of running a "single-issue campaign" while ignoring issues such as national security and the threat posed by terrorists in the Middle East. "You can maybe get away with that if the other issues out there are health care and the economy," Gage said. "But with foreign policy, when they're fearful for their families and the only issue Democrats are talking about is birth control and abortion, there could be a backlash."

In North Carolina, a recent ad from Tillis criticized Hagan for failing to address new terrorism threats. Other recent GOP advertising in the state seemed notably targeted toward women, too. The latest spot from Crossroads GPS featured a woman criticizing Hagan's positions on health care before praising Tillis's and touting his work on health insurance for autistic children. More and more Republican TV ads have prominently featured women making their case in 2014, a purposeful shift, according to GOP ad-makers. On a more unusual level, the College Republican National Committee just released digital ads touting GOP gubernatorial candidates with a "Say Yes to the Dress" theme to "start the conversation" with young women voters, according to the group's chairman.

That's all part of a serious push among Republicans to win back a segment of the female vote—which, according to the polls, is the only thing standing between the GOP and a wildly successful November.

{{thirdPartyEmbed type:interactivegooglecharts source:https://docs.google.com/spreadsheets/d/1X81UF8YIMJUJRG8nj9EoGvIkUdJvNt12oOpyITBzmDE/pubhtml?gid=0&single=true}}

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.