By Amanda Becker

DES MOINES, Iowa (Reuters) - If Hillary Clinton pulls off a victory in her close race for the Democratic presidential nomination with Bernie Sanders, she will have women like Joan Pinnell to thank.

Pinnell, a 32-year-old Chicagoan and former volunteer for Barack Obama's 2008 campaign, has been knocking on doors in Iowa in support of Clinton, Obama's Democratic former rival. Her dedication stems in part from the desire for a president who can "personally understand the struggle that it is to be female" – a factor that was far less important to her back in 2008 when she was in her mid-20s.

"I get annoyed when I hear women say 'it doesn't matter at all,'" Pinnell says of the gender issue. "It matters."

With Iowans ready to cast the first votes of the 2016 presidential race on Monday, polls show Sanders and Clinton locked in a statistical dead heat in the state, although she leads the U.S. senator from Vermont in national polls.

The enthusiasm that Sanders has sparked with college students and those just out of college – including young women – has generated buzz around his campaign. What has gotten far less attention, however, is the split that exists between women in their late teens and early 20s and their cohorts in their 30s. 

Though Democratic women aged 18 to 29 say they prefer Sanders to Clinton 57 to 24 percent, those aged 30 to 39, like Pinnell, prefer Clinton to Sanders 45 to 28 percent, according to a Reuters/Ipsos tracking poll of 3,466 respondents taken from Jan. 1 to Jan. 26. (Graphic: http://tmsnrt.rs/20bI5ry)

In interviews with women voters aged 30 to 39 nationally, many said that in 2008 they had been drawn to Obama's idealistic message of "hope" and "change," but this time around they say they value the experience of Clinton, a former first lady, senator and secretary of state.

After navigating their first apartments, careers, moves, marriages and children, these women also said they like Clinton's emphasis on issues such as reproductive health and equal pay for women.

Still, Sanders' fiery rhetoric and liberal agenda are drawing support from young women like Abigail Gill, 19, a student at Keene State College in New Hampshire, who say gender does not matter.

"To vote for Hillary just because she is a woman is just as bad as not," Gill said.

'A NEW PERSPECTIVE'

Clinton played down her gender in 2008 but this time around urges voters not to miss the chance to make history by electing the first woman president.

She has worked hard to court women "Millennials" – the generation born beginning in the early 1980s.  She taped an episode of "Broad City," a sometimes raunchy comedy about two twenty-something women living in New York City and has created a "girl power" music playlist. She makes a point of calling on young women at town hall events and takes countless "selfies" with them.

Clinton's senior aide and protégé, Huma Abedin, 39, headlined a New York City networking event for women. Clinton's daughter, Chelsea, 35, has hosted a fundraiser at the trendy workout spot SoulCycle.

Kellie Lewis, 36, brought her 19-month-old daughter and 5-month-old son to hear Clinton speak at a bowling alley in Adel, Iowa last week. Lewis said she is eager to help make history by supporting Clinton.

"I feel like we've had men looking at government for so long, a new perspective is exactly what is needed to get a more equal society," Lewis said.

But Erin Batchelder, a junior at Smith College in Massachusetts, is conflicted. She says she'd like to see "one of my own" in the Oval Office but is drawn to Sanders, a self-described democratic socialist whose message centers on fighting income inequality and the excesses of Wall Street.

Batchelder plans to vote for Sanders but her best friend, also a Smith student, recently switched from backing Sanders to supporting Clinton.

"That's what I'm grappling with right now, especially with my best friend making that shift, a lot of women at Smith are making that shift," Batchelder said.

(Editing by Caren Bohan and Mary Milliken)

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