WASHINGTON -- On the way to a dinner party in Seattle last month to raise money for her Off the Sidelines PAC, Sen. Kirsten Gillibrand made an unannounced stop at a local bar for a "Ready for Hillary" rally.

There, more than 100 women who had paid $20.16 to urge Hillary Clinton to run for president clapped as Gillibrand spoke about her women's agenda and the steps they could take to get involved in politics.

"She spoke just enough to level the challenge 'to get your booties moving,' " said Seattle political strategist Cathy Allen. "And she spoke about how great it would be to have Hillary as president."

That was just one of many stops Gillibrand has made across the country as she builds a national profile as a champion for women through her leadership PAC, Off the Sidelines, which is separate from her campaign committee.

Secure in her seat with the back-to-back elections of 2010 and 2012 behind her and her next race not until 2018, Gillibrand is building a nationwide network to become more than just Clinton's Senate replacement.

She has boosted her visibility with a much-publicized battle over military sexual assault, placed women at the heart of her legislative agenda and has used Off the Sidelines to channel $3.1 million to Democratic female candidates.

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More than anyone else, Gillibrand has positioned herself to be both a booster and beneficiary of the excitement among women for a Clinton campaign for the White House, said Debbie Walsh, director of Rutgers University's Center for American Women and Politics.

"She is tapping into an energy and excitement about . . . women running for high-level leadership positions," Walsh said. "She's figured out a way to benefit the cause and to benefit herself at the same time."

To brand herself as the champion for women, Gillibrand titled her book coming out in September "Off the Sidelines: Raise Your Voice, Change the World."

"That's who I am," she said.

A call for women

Gillibrand said she created Off the Sidelines as a website in July 2011 -- a call on women to vote and run for office after the 2010 election reduced their numbers in Congress.

She said it was an extension of individual help she's given to others, patterned after Clinton's help for her own first run for the House in upstate New York in 2006.

"Women have the power to shape the future, it's just a matter of getting off the sidelines and getting involved," Gillibrand said.

In 2012, she turned Off the Sidelines into a leadership political action committee whose purpose is to raise and give money to others. It can't pay for her own races.

Gillibrand already had a leadership PAC called Empire, so she now has "his and her" PACs: Empire gives to men, Off the Sidelines to women.

Since January 2013, Off the Sidelines has raised $3.1 million, the second most of any leadership PAC, records show.

It spent half, $1.5 million, on expenses. That's largely for the fundraising team of three staffers and consultant Anne Lewis, a former Hillary Clinton aide, that she moved to the PAC from her Senate campaign after she won a six-year term.

Its fundraising is distinctive.

Most leadership PACs, including Empire, rely on business and interest group PACs for nearly all their funds.

Off the Sidelines gets 95 percent of its cash from individual donors -- and the Center for Responsive Politics, a research group, said 52 percent of them are women, more than for any other comparable PAC.

It has contributed $519,000, mostly to female candidates. Only one other leadership PAC has given more to Democrats in this election cycle. With $1.2 million in cash, Off the Sidelines is poised to give more.

But the fundraising team does more than raise money for the PAC, spokesman Glen Caplin said. Since 2011, he said:

It raised nearly $1.6 million with weekly emails that led to online donations through the ActBlue website for contributions for Democratic women in tight races.

It collected $372,000 from Gillibrand's New York donors, 60 percent of them women, at four different joint fundraisers for 12 female candidates.

And it helped candidates raise $644,500 by sending Gillibrand to headline fundraisers.

Gillibrand said she has a goal of raising $2 million for female candidates this year -- so far she's raised $800,000.

"The most powerful part of Off the Sidelines is that it is a network," Gillibrand said. "It's really about starting a national conversation."

To build that network, the PAC has paid for Gillibrand's travels to San Francisco and Seattle, Chicago, Boston, Philadelphia, New York and Miami. She even went to London.

Gillibrand concedes what political analysts around the country say: She's well known among big donors but not by voters outside of New York.

So she's building an email list to boost her name recognition as she taps donors for others.

She won't say how big the list is, but Caplin noted Off the Sidelines had more than 12,000 small-dollar donors in 2013.

She insists her events draw both Democrats and Republicans, and that she wants more women of both parties in Congress.

Women can work together, she said, and they would change the debate from issues like restricting abortions to creating jobs and helping families.

Yet her agenda -- paid family leave, affordable child care, universal pre-K, a raise in the minimum wage and equal pay -- is from the Democratic playbook.

And Gillibrand and her PAC donate only to Democrats.

Conservative women and most female Republican candidates oppose her proposals.

"I'm tired of the continuing painting of women as victims and that those of us who don't believe in big government are waging a war on women," said Carrie Lukas of the Independent Women's Forum.

Gillibrand said most women agree with her agenda, and Walsh and other experts say its focus on women is smart.

Studies show female politicians must rely on female donors, even though fewer of them make donations than men and those who do give less.

An appeal to women now taps into a surge of interest in politics in anticipation of a Clinton presidential run, as shown by Emily's List, the biggest women's PAC. It said its membership jumped from 2 million to 3 million last year and it's setting a new fundraising record.

Other women in Congress also raise money for female candidates and sponsor bills to help women. But Walsh said of Gillibrand, "She's putting herself out there as the woman in the Senate who is making this a priority."

Few doubt her sincerity in wanting to elect more women.

But records show she has always used Off the Sidelines to also raise money for herself.

At first she was the main beneficiary of Off the Sidelines donations when it was just a website. Now that it's a leadership PAC, when donors click on the link in her emails soliciting funds for others, they have the option of giving to her campaign or PAC as well.

And Walsh said the network of female elected officials Gillibrand has helped raise money for will be a big help to her if she runs for national office.

Higher office?

Gillibrand, 47, has been mentioned as a potential candidate for governor of New York or the White House. But she sidesteps questions about her future, saying she backs Clinton for president.

But is she Hillary Clinton's political heir? Gillibrand said, "That's not who I am."

The only benefit from Off the Sidelines she acknowledged is a legislative one.

She said after she helped long shot candidate Tulsi Gabbard win a seat in Congress from Hawaii in 2012, Gabbard sponsored her military sexual assault bill in the House.

That hasn't always worked.

Gillibrand raised $220,000 for Sen. Claire McCaskill (D-Mo.) for her race in 2012, Caplin said. And McCaskill helped block that same bill in the Senate.

Unlike men, women must be asked and encouraged to run, said Rebecca Sive, author of "Every Day is Election Day," a how-to-run book for women.

That's exactly what Gillibrand did, said Nassau County District Attorney Kathleen Rice, who is running to replace retiring Rep. Carolyn McCarthy (D-Mineola).

"When I was deciding to run, I don't think there was anyone who made as strong a pitch as Sen. Gillibrand," Rice said.

Rice said Gillibrand has been there at every step: a $10,000 donation the day after she announced, an endorsement two weeks later and a speech at a fundraiser earlier this month.

Rice said she tries to be a role model, just like Gillibrand.

"I don't think there is anyone who is more committed to that than Sen. Gillibrand," Rice said. "She is really leading the charge."