Four years ago, women voters supported Obama over Republican John McCain by 56 per cent to 43 per cent. Among men, the Democrat led McCain by just 49 per cent to 48 per cent.
But women's enthusiasm for Obama as president has slipped this year, making his road to re-election more difficult.
He is narrowly favored to win the female vote, but in many national polls, the incumbent's lead over Republican Mitt Romney among likely women voters has dipped to single digits. Reuters/Ipsos polling data last week had it at nearly 5 percentage points. He trailed among likely male voters by about 6 points.
Republicans point to Romney's gains with women since his strong performance in the first presidential debate on October 3.
Marguerite Hunsinger, 59, of Flagler Beach, Florida, who had been undecided, said the debate shifted her to Romney's camp.
"I'd been very, very skeptical about Romney," said Hunsinger, a self-described homemaker. "And I just thought he acted very presidential and capable, and he had answers that I agreed with more."
In contrast, she said Obama "was like asleep. It felt like he was just wasn't there."
Romney's camp accuses Democrats of condescending to women by overemphasizing issues like contraception when polls show men and women both care more about jobs and the economy.
Democrats note that Obama continues to hold significant leads among women in the decisive swing states and say the women's vote will help propel him to victory.
Women comprise more than half of the U.S. electorate, and in presidential elections, about 7 per cent more women vote than men.
'WOMEN'S ISSUES' BOOST OBAMA
Democrats insist that Obama outshines Romney on many issues important to female voters, from healthcare to education, equal pay and fair taxes.
Evelyn Miranda, 47, of Hialeah, Florida, said she had been undecided, but recently embraced Obama because of his positions on social issues and insistence that the wealthy pay higher taxes.
"He wants to tax people more who make more money. I am really for that a lot," she said.
Miranda, an artist and teacher, also said she worried that Republicans might ban abortion, a position with which she disagrees after experiences with student sexual abuse survivors.
Obama's current support margin among women is not only below his own 2008 performance but that of Al Gore in the 2000 election. Gore, then the Democratic vice president, narrowly won the popular vote but lost the Electoral College to Republican George W. Bush.
"Certainly, team Obama would like to see their national margin among women higher," said Tufts University political scientist Richard Eichenberg, who is tracking this year's gender gap and estimates Obama's lead among women nationally at 8 percentage points.
"In 2008, he had an extra cushion when he won big (+13 among women), and Gore won narrowly with +11. So I think that they would like that 8-point number a little higher," Eichenberg said.
But Obama's standing among women remains strong in the battleground states he will need to clinch all-important electoral votes. "He leads among women by large margins in virtually all the swing states," Eichenberg said.
For example, in Ohio, Eichenberg noted polls during October showed Obama with a 12-point lead among likely women voters.
Romney's solid showing - and Obama's poor one - in the first debate in Denver upended the presidential race. Obama had been building a lead before he and Romney first went head-to-head. Romney has since gained steadily in the polls.
For the week ended September 30, just before the debate, Reuters/Ipsos poll data showed Obama leading Romney by 52 per cent to 41 per cent among a sample of 1,022 likely women voters. He also led among likely men voters, by 47 per cent to 44 per cent.
Last week, Obama led Romney among likely female voters by 48 per cent to 44 per cent, and trailed among likely male voters by 50 per cent to 44 per cent, the Reuters/Ipsos data showed.
JOBS, JOBS, JOBS?
Obama's team has courted women with ads stressing his support for equal-pay legislation, abortion rights and contraceptive insurance coverage. The Democratic National Convention featured high-profile women emphasizing those issues.
They slammed Romney for shifting positions on abortion and contraceptive rights since his 2002 election as governor of Democratic-leaning Massachusetts and for failing to support Obama-backed legislation easing the way for women to sue over workplace pay discrimination.
But some analysts said that approach might help explain Obama's flagging support, in a year when economic problems and a high jobless rate worry voters.
"The Democrats have been very focused on what we call the particularistic concerns of women, such as abortion, equal pay and contraception," said Lara Brown, a political scientist at Villanova University.
"I'm wondering if the women who are migrating toward Romney, they're just saying to themselves, 'Abortion and birth control and equal pay are not my issues, what I'm more concerned about is the overall state and health of the economy.'"
Marion Kirschner, 33, of Delaware, Ohio, placed herself among those voters.
The Romney supporter called herself "kind of liberal" on social issues like abortion and gay marriage rights - which Romney opposes - but said government should focus elsewhere.
"I think the government should worry about the economy, domestic issues and foreign policy. That is more important to me than social issues," said the married mother of 17-month-old twins, who works at an aviation company.
Vicki May, 43, of Colonial Heights, Virginia, said she hoped Romney would improve the economy, while expressing anger with Obama.
"I've been out of work for three years and I haven't been able to find anything," she said. "They keep saying there are jobs out there, but I haven't noticed."