WASHINGTON » Rick Santorum speaks out against prenatal testing. Virginia’s governor and Legislature get caught up in an emotional debate over whether women seeking abortions should be required to undergo an ultrasound. President Barack Obama, under pressure, recalibrates his position on health insurance coverage of contraception for employers with religious affiliations.

Social issues are back with a vengeance, dominating the dialogue on the presidential campaign trail, in Congress and in state capitals.

In an election that until now has been almost totally defined by the economy’s struggles, the abrupt return of the culture wars has introduced a volatile new element. The politics may play out in any number of ways, but perhaps the biggest question is the effect on a crucial swing group: moderate and independent female voters.

Even before social issues were forced front and center by the combination of Santorum’s new prominence, the recent battle over the Susan G. Komen Foundation’s financing of Planned Parenthood and Obama’s decision to revise his contraception policy, both parties were tracking the sentiments of women closely.

Recent comments by Santorum about female soldiers not belonging in combat and the role of "radical feminism" in encouraging work outside the home only fueled the sense that the election could present women with stark ideological choices about their rights and place in society.

Democrats, including Obama, have traditionally relied heavily on the female vote. From 1992 to 2008, Democrats won the overall women’s vote in every presidential election, with Obama defeating Sen. John McCain four years ago 56 percent to 43 percent among women, according to exit polls. (Republicans have tended to win white women and married women, with Democrats winning nonwhite women and single women.)

But in the 2010 midterm election, women, who vote in greater numbers than men, swung to Republicans, if barely, cutting deeply into the core of Obama’s electoral coalition. There are now signs that Obama is winning women back. In a /CBS News poll this month, Obama came out well ahead of Mitt Romney among all women in a head-to-head matchup (53 percent to 37 percent) and held him to a draw even among white and married women. Obama held much the same advantage over Santorum, who has trailed Romney among female voters in some polls looking at state primary contests.

Social issues provide both parties a chance to rally their ideological bases, but it is less clear how the issues play among moderate and independent women. Catholic women, who swung for Obama in 2008 and then for Republicans in 2010, now support the administration’s stance on contraceptive health coverage, according to the /CBS News poll.

Democrats say that they plan to use the issue to help convince women, especially independents, that Republicans are moving so far to the right generally that they are no longer an acceptable alternative to run the country.

"When Republicans focus in a very extreme way on these kinds of issues, it focuses more attention on the problems with the Republican brand," said Anna Greenberg, a Democratic pollster. "It becomes part of a larger narrative about Republican leadership and a referendum on Republican leadership over the last year and a half."

Independent women "are turned off by extremism," Greenberg said. "As a targeted message to independent women, it can be very effective."

Even in 2010, when the economy and anger over the health care law and the bailouts were driving politics, Democrats invoked social issues in the closing stages of some races where they felt the Republican opponent could be labeled extreme.

The Democratic Senatorial Campaign Committee, seeking to appeal to female voters on behalf of Michael Bennet, who was running for the Senate in Colorado, ran a commercial against his Republican challenger, Ken Buck, a Tea Party favorite, highlighting Buck’s stances against contraception and abortion rights. (Bennet won by less than 2 percentage points.)

In Arizona, Rep. Gabrielle Giffords ran a commercial in the closing days of her 2010 election campaign that called her Republican opponent, Jesse Kelly, "dangerous," in part because of his opposition to abortion rights.

But while social issues inspire passionate reactions on the ideological wings of the two parties, they tend not to be seen as priorities among the vast pool of voters in the middle — especially at a time when the economy remains far and away their main concern.

"You rarely ever see social issues come up as one of the most important issues facing the nation," said Karlyn Bowman, who studies public opinion as a senior fellow at the American Enterprise Institute, the conservative research group. "Historically, while they have been big and divisive issues in some governor’s and Senate races, they tend not to be very important on a national level."

More to the point, some Republicans said, the surge of attention to these issues could prove to be brief, fading quickly if Romney can dispatch Santorum relatively soon and return the focus of his campaign to Obama’s performance on creating jobs.

"If Rick Santorum is not the nominee, all the attention to these issues is going to evaporate," said Whit Ayres, a Republican pollster. "The probability of social issues playing a significant role in the general election is minimal."

The idea that social issues will brand Republicans as extremists in the eyes of independent and moderate voters is "a Democratic fantasy," Ayres said. "What will drive independent voters is whether they see improvement in the economy and progress in stopping the relentless expansion of federal spending and deficits and keeping us from going the way of Greece."

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