Women could well swing the outcome of the US presidential election, and both candidates know it, playing up issues like healthcare and abortion in the countdown to November 6. Women make up 53 percent of the electorate in the United States and they vote in greater numbers than men, political analysts say. They also make up a higher number of undecided and swing voters. "In a very close election, with almost 10 million more women voting than men, the gender gap can make a difference in the outcome of the election," said Debbie Walsh of Rutgers University's Center for American Women and Politics. Both men and women agree the economy is the number-one issue. But women are more likely to attach greater importance to government playing a bigger role in social policy -- something President Barack Obama supports, and Republican challenger Mitt Romney opposes. "What really drives the gender gap are attitudes about welfare and the social safety net," said Melissa Deckman, a political science professor at Washington College in Maryland specializing in gender and politics. The gender gap -- the percentage of women versus men who favor a candidate -- ran strongly in Obama's favor in 2008 when he raked in 56 percent of the women's vote, a seven-point edge over Republican rival John McCain. This time around, however, Romney is going all out to nibble away at Obama's lead, which in some opinion polls has fallen to as little as three percentage points this month. "Before Mitt Romney started to make some inroads among women, I think the Obama campaign probably thought the women's vote could have carried them to victory pretty easily," Deckman said. Obama makes a direct link between women's economic well-being and his health care reforms. Romney has vowed to dismantle "Obamacare" if he takes office, and to halt federal funding for Planned Parenthood, the nation's leading abortion provider especially to lower-income women. "It's an economic issue for women," said the president on the campaign trail the other day, defending his health policy. "It makes a difference. This is money out of that family's pocket." On Friday, the Obama camp put out a video aimed at first-time women voters featuring Lena Dunham, star of the hipster TV series "Girls," who likened the president to the perfect guy who "really understands and cares about women." "Your first time shouldn't be with just anybody," she deadpans. Romney, who has spent much of his long-running campaign wooing social conservatives, has meanwhile sought to turn voters' minds away from abortion as election day nears. One TV ad features a soccer-mom narrator explaining that Romney still accepts the termination of a pregnancy in instances of rape, incest or when the mother's life is in danger. But then she adds: "I'm more concerned about the (national) debt our children will be left with. I voted for president Obama last time, but we just can't afford four more years." In some voters' eyes, Romney wasn't helped earlier this week by US Senate candidate Richard Mourdock's assertion that a pregnancy resulting from rape was "something that God intended to happen." "Pretty upsetting," said Courtney Kelly, 24, an undecided voter in the battleground state of Nevada. Michael Dimock of the Pew Research Center in Washington said that if women doubt either candidates' ability to turn the economy around, their decision on voting day could be swayed by non-economic concerns. "They may look down the list and consider an issue the president can do something about because it's one that they can see a great deal of daylight between the candidates," he said.