New Jersey Gov. Chris Christie’s wife, Mary Pat, who was standing behind Trump, appeared to react negatively as he made the comments.
The episode is the latest in a long line of Trump remarks widely seen as sexist or offensive toward women, and it underscores the serious difficulties Trump will face in garnering support from female voters if he is the GOP nominee.
The Clinton campaign responded early Wednesday morning with an online video showing footage of Clinton dismissing Trump's comments on her gender during a campaign rally.
"Mr. Trump accused me of playing the 'woman card.' Well if fighting for women's health care and paid family leave and equal pay is playing the 'woman card,' then deal me in.'
Although women’s issues have received relatively little attention in the Republican primary, Trump’s low favorability among women nationwide reveals what would be a crucial weakness for the billionaire if he secures the nomination.
Trump doubled down on his comments Wednesday during a series of morning television interviews, dismissing critics who called the remarks sexist and instead criticizing Clinton’s tone.
"It's not sexist. It's true. It's just a very, very true statement. If she were a man, she'd get 5 percent. She's a bad candidate. She's a flawed candidate," Trump said on ABC’s “Good Morning America” on Wednesday morning. "She's not going to do very well in the election, and I look forward to showing that.
“I haven't quite recovered, it's early in the morning, from her shouting that message,” he said on MSNBC’s “Morning Joe.” “And I know a lot of people would say you can't say that about a woman because, of course, a woman doesn't shout, but the way she shouted that message was not — ooh."
“I guess I'll have to get used to a lot of that over the next four or five months,” he added, also saying that he expects to do well with female voters.
The real estate mogul has won women voters on average by 10 percentage points over his rivals in Republican primary contests this year, and on Tuesday, he won by more than 20 points among female voters in Connecticut, Maryland and Pennsylvania.
But Trump’s successes in winning Republican women has not translated to popularity with women or men in the broader electorate, where he continues to be deeply unpopular.
A USA Today-Suffolk University poll released this week found that 66 percent of likely female voters nationwide have an unfavorable view of Trump, compared with 48 percent who have a negative opinion of Clinton. And women are far more likely to have intensely negative views of Trump. A Washington Post-ABC News poll earlier this month found that 64 percent of women feel “strongly unfavorable” toward Trump, compared with 41 percent of men.
Clinton, meanwhile, appears poised to become the first female presidential nominee for a major political party. Clinton strategists think women are likely to be the key to a general-election victory for the former secretary of state, including independent and moderate Republican women motivated to vote for the first female president or because they are turned off by Trump or his chief rival, Sen. Ted Cruz of Texas.
Clinton has built a 2016 campaign focused on issues of keen interest to women voters, including equal pay, health care and paid family leave. Her economic plan promises to “lift up participation in the workforce — especially for women.”
After deliberately playing down her gender in her loss in the 2008 race, Clinton now talks freely of her own experiences in the workplace and in politics. She often speaks of breaking “that highest, hardest glass ceiling” of electing a female president, and she jokingly tells audiences that after more than 200 years and 44 male presidents, “it’s time.” She also gushes about being a grandmother and jokes about coloring her hair.
Even when discussing issues such as gun control, immigration or the minimum wage, Clinton often uses women as her examples. She held small-group discussions in Pennsylvania and Connecticut ahead of Tuesday’s primaries where the only participants were women.
She has collected the endorsements of Planned Parenthood and Emily’s List, among other organizations. And those groups have already joined her in highlighting the historical nature of her candidacy and characterizing the Republican party as anti-women.
“The Republican candidates are achieving new lows every day -- suggesting women be punished for their health care decisions,” Planned Parenthood President Cecile Richards said in a statement Tuesday night. “Hillary is showing us that a world of love, kindness, and real policy solutions — no matter where you live — is the right vision to move our country forward.”
What Donald Trump is doing on the campaign trail
Yet gender politics have at times been tricky for Clinton, who has been losing against her Democratic primary rival, Sen. Bernie Sanders, among younger women voters.
Shortly before the New Hampshire primary, those generational tensions were brought to the surface when former secretary of state Madeleine Albright, appearing at a rally with Clinton, declared: “There's a special place in hell for women who don’t help each other!”
It was a line that Albright had used often in the past, usually to a burst of applause, but it took on a different meaning in the context of a hard-fought primary. Albright later apologized in a New York Times op-ed headlined “My Undiplomatic Moment,” where she wrote: “I did not mean to argue that women should support a particular candidate based solely on gender.”
And in 2008, Geraldine Ferraro — who made history in 1984 as the first woman to be named to a major party’s presidential ticket — had to step down from her fundraising role in the Clinton campaign after she suggested that Barack Obama was beating Clinton in the Democratic primary only because he was black.
“If Obama was a white man, he would not be in this position. And if he was a woman of any color, he would not be in this position,” Ferraro said in an interview with a California newspaper, the Daily Breeze. “He happens to be very lucky to be who he is. And the country is caught up in the concept.”
Trump has frequently come under fire for his attitudes on women. Earlier this year, Trump retweeted an unflattering photograph of Heidi Cruz, the senator’s wife, to his more than 7 million Twitter followers, comparing her with his own wife, former model Melania Trump. The caption read, “A picture is worth a thousand words.”
Donald Trump said the move was in retaliation for racy images of his wife distributed by a pro-Cruz super PAC. But the retweet spawned widespread outrage and condemnation from Cruz.
In another instance last month, Trump walked back his comment that women who have abortions should be punished if abortions are made illegal. His campaign later said only physicians performing the procedure should face punishment.
Until the end, Trump was relatively muted during much of his Tuesday news conference, bragging about his dominance in the race and navigating tricky questions about vice presidential picks and immigration rates. But when asked specifically about Clinton and the “women’s card” in the final question of the evening, Trump made his remarks suggesting that being a woman was Clinton's main advantage.
The reaction of Democrats was typified by a tweet from former Obama communications chief Dan Pfeiffer: “Because being a woman has historically been a huge advantage over billionaire white males."
Gearan reported from Washington. Emily Guskin in Washington contributed to this report.