State Sen. Joni Ernst is the only woman running in a crowded primary race for an open Senate seat in Iowa.  The primary is June 3. (Bill Neibergall/The Des Moines Register via AP)

Democratic women are running hard on equal pay as an issue that could drive women to the polls in this fall’s elections for U. S. Senate and House. But Republican women think they have an equally emotionally-charged issue that resonates with voters, particularly women: the Affordable Care Act.

In contests in Michigan, West Virginia and elsewhere, candidates are calling attention to consumer’s complaints with the health care law, noting that women are particularly impacted because they often are in charge of making health care decisions for their families.

Yet, Republican women are not emphasizing their gender as they ask for voters support, even in races where they could make history.

Joni Ernst, who is running for the GOP nomination for Senate in Iowa, describes herself on her campaign bio page as “Mother. Soldier. Conservative for U.S. Senate.”

Even though Iowa has never elected a female member of Congress, Ernst, currently a state senator who also serves in the Iowa National Guard, said she is not running on gender.

“It would be historical, but it’s not part of my pitch,” she said of potentially becoming Iowa’s first female senator. “I don’t believe we should vote for somebody based on gender, we vote for the right person and I’m the right person to go to Washington, D.C.”

“Of course I’m always very diplomatic in the way that I attack any issue and I think that’s appealing to women. Be straight-forward about [issues], but be compassionate, show them that this is something that really matters to Iowans, not just female but also males,” she said.

Ernst has been endorsed by former Republican presidential nominee Mitt Romney and RightNow Women PAC, a group that aims to boost the engagement level and electoral chances of young Republican women. 

She is one of a half dozen GOP women in high profile races that could tip the balance of the Senate. Her run comes as Republicans are grappling with closing a gender gap that is particularly pronounced among single women, a demographic that proved crucial in the 2012 campaign and in the Virginia gubernatorial election in November 2013.

The Senate race in West Virginia, where Secretary of State Natalie Tennant and Rep. Shelley Moore Capito will likely face each other — a rare general election match-up between two women candidates — highlights the different ways that Republican and Democratic women are campaigning.

Tennant, the Democrat, has slammed Republican Capito for her votes against legislation like the Lily Ledbetter Fair Pay Act.  In February, the Tennant campaign launched “Women for Natalie,” framing her as a champion for women and families and highlighting her support for Social Security, equal pay legislation and a minimum wage hike.

Democrats see equal pay as one of the clearest ways to distinguish themselves from Republicans, who generally do not support laws that would guarantee women earn the same as men in comparable jobs.

“There are few issues that show the contrast between Democrats and Republicans as clearly as equal pay,” said Stephanie Schriock, president of Emily’s List. “Democratic candidates, especially Democratic women, are running for office to give women and families a fair shot. Republicans are not only opposed to improving the gap, they are actively repealing equal pay legislation. Their stance on equal pay exposes just how out-of-touch Republicans really are.”

Chuck Flannery, Capito’s political director, said the West Virginia congresswoman has been long supportive of women’s issues, and her campaign in the Senate carries on the same tradition. Capito has pointed to Obamacare as particularly harmful to women in West Virginia as well as environmental restrictions on coal.

“To put it simply, women’s issues are West Virginia’s issues. It’s about energy, healthcare, jobs, education and a better economy,” Flannery said. “Our goal should be to providing opportunity, a better future for women, their families and their children.”

The troubled roll out of the Affordable Care Act is an issue that GOP candidates believe they can use to return fire on the criticism that the party is hostile to women.

In Michigan, Republican Terri Lynn Land, running in a close race for another open Senate seat,  marked the anniversary of the Affordable Care Act and stressed her opposition by highlighting the voices and stories of women who said they were negatively impacted by the law. That strategy also is being used by Americans For Prosperity, a conservative nonprofit backed by the Koch brothers, that has also used women as the face of their ads attacking the health care law.

Jennifer Stefano, regional director for Americans for Prosperity, said they have run ads designed to appeal to women because “women carry the burden of failed economic policies.”

“It’s not just dropping an ad, we are backing up with a real grassroots effort,” she said. “We are doing the ads to do some level of education for women on what is happening, particularly with Obamacare and how it’s negatively impacting their lives, but then we follow it up with how they can do something about it.”

Republican Mia Love, who could face Democrat Doug Owens for an open House seat in Utah and has two challengers for the GOP nomination, said that in conversations she has had with women, the Affordable Care Act invariably comes up, with women telling stories of being kicked off insurance plans. But Love said she is approaching her race “wholistically,” and not just focusing on “women’s issues.” She is however quietly making a specific push tailored to women.

“I go out and tell them they should have a seat at the table and that there are too few women involved… We have to have equal involvement. I tell women that if they don’t get involved and stand up and get involved in the process, they run the risk of somebody inferior making the decisions for them and someone who might not be able to relate,” she said.  “As we get more women involved, we will find the solutions to the problems that affect all of us.”

Republican pollster Kellyanne Conway said reminding both genders of the problems with the Affordable Care Act would trump Democratic attacks on the equal pay issue.

“Republicans recognize that this is also the Democratic party’s latest attempt to cry ‘squirrel!’ so women in this country, who control two out of every three health care dollars that are spent and are disproportionately health care consumers and providers… divert their attention from the unspooling of Obamacare,” Conway said.