Record numbers turn out to send more women than ever to Congress in powerful snub to conservatives' 'war on women'

Election 2012 is already being billed as a historic moment for women. Their votes re-elected Barack Obama for a second term, sent more women than ever before to Congress and delivered a powerful message to conservative politicians that attempts to redefine rape or interfere with hard-won reproductive and other rights will not be tolerated.

Women voted in record numbers, and the gender gap between the two candidates could not have been more profound. Unmarried women backed the president by an incredible 38 percentage-point margin over Romney, a statistic which was one of the most striking of Tuesday night.

But the driving force behind female voters was not so-called "women's issues" – it was the economy.

Terry O'Neill, president of the National Organisation for Woman, said: "It is economic issues. Sure, at a certain point it's also about rights, but at a more immediate level it's about survival.

"When you look at unmarried women, they are very often the head of their families or taking care of elders. What they saw in Mitt Romney was someone who had disdain for them – as part of the 47%. He wanted to cut after-school programmes, Head Start, food stamps and job training programmes."

She said that the Republican's so-called "war against women" including Romney's pledge to get rid of Planned Parenthood, a key women's healthcare provider that also provide abortions, was important to unmarried women for economic reasons.

"Planned parenthood offers medical services at a low price. When you are struggling economically, that sort of thing is your bread and butter. Two-thirds of minimum wage workers are women – and the minimum wage has not gone up in the last few years," O'Neill said. "If you don't have access to reliable reproductive healthcare you are going to have a hard job surviving. One in three women under the age of 45 in the US have an abortion. It's common and it's necessary."

Women gave Obama 55% to Romney's 43%, a proportion that was unchanged from the president's lead among women in 2008.

During the 2012 election campaign, the Republican party has been accused of a "war against women" over issues like birth control and abortion. It has come to a head countless times, but most prominently after comments by senior Republican candidates which caused widespread offence.

Todd Akin, running for the US senate in Missouri, suggested that women had biological ways to "shut down" pregnancy after a "legitimate rape", a claim made to support his opposition to abortion in any circumstances including pregnancy from rape. Richard Mourdock, the Republican Senate candidate in Indiana, said that pregnancies resulting from rape "is something that God intended to happen". Both men were defeated by their Democratic opponents.

Lisa Maatz, the policy director of the American Association of University Women, which published recent research showing a massive gender gap in earnings over time between college men and women, said that 2012 was a wake-up call for young women.

"In this election, young women really understood what their mothers have been saying about the rights they have fought for," Maatz said. "They are not set in stone. When young women hear politicians say that birth control should be illegal – like Rick Santorum did – and all-male panels talking about birth control, it all adds up.

"But these unmarried women are not all young women, they are all ages, and some of them are worried about social security and medicare. What they have in common is they are more economically vulnerable."

Birth control was a "huge economic issue" said Maatz. "Women did not vote with their ladyparts, they voted with their pocketbooks like they always do".

Among those joining the Senate will be Tammy Baldwin, of Wisconsin, who made history twice over. She will be the first openly gay member elected to the Senate and the first Wisconsin woman elected there.

In New Hampshire, voters elected a female governor, and becomes the first state with an all-female congressional delegation. Carol Shea-Porter and Ann McLane Kuster, Democrats, defeated Republican incumbents on Tuesday night to win the state's two House seats. They will join the state's senators, both women, Jeanne Shaheen and Republican senator Kelly Ayotte.

Maatz said: "I don't know what they put in the Kool-Aid in New Hampshire, but I want some."

Celinda Lake, Democratic pollster and president of Lake Research Partners, said it was a "historic election for women" in a number of ways. "It proves that you don't make women angry."

She said that women's votes drove a number of women – at the last count 20 – to the Senate, and also won the races for Claire McCaskill, who was up against Akin and Joe Donnelly, who was up against Mourdock, after both men were widely criticised after making comments on abortion and rape.

Exit polling showed that McCaskill had more of the female vote than she did in 2006 and it was overwhelmingly from women aged between 18-44. A majority of Missouri voters supported abortion and three-quarters of Missouri voters came out for McCaskill.

Polling for the Donnelly/Mourdock contest showed a similar pattern.

Fifty-two per cent of women voted for Donnelly in Indiana, with 42% voting for Mourdock. Male voters were almost deadlocked, according to the Washington Examiner.

The election result could also leave a profound impact on reproductive rights indirectly through the supreme court. Four of the current justices - Ruth Bader Ginsburg, Anthony Kennedy, Antonin Scalia and Stephen Breyer – are all in their 70s, so its seems likely that the president over the next four years will get to nominate at least one and quite possibly two replacements. A Romney win could have led to the court being tilted decisively against Roe v Wade, the landmark 1973 decision guaranteeing the right to abortion under most conditions.