A large majority of the big donors to the pro-Hillary-Clinton super-PAC Ready for Hillary are women, bucking a wide trend in politics that typically sees men give more than women.
Women gave $507,000 in donations over $200, while men gave $491,000.
The female donors helped the group raise $1.25 million in the first half of the year.
The fact that more women than men gave big-dollar sums to the super-PAC makes it unusual among most outside spending groups, which typically see men donate with higher frequency and in larger sums.
A Sunlight Foundation analysis found that only 28 percent of the top 31,000 donors during the 2012 cycle, giving $12,950 or more, were women. And last cycle, only 11 of the top 100 donors were women, and they gave less than 20 percent of the overall sum contributed by the top 100.
Those numbers don't include contributions to 501(c)(4) nonprofit groups, which aren't required to disclose their donors.
Two other prominent super-PACs had mostly male donors. Kentuckians for Strong Leadership, which is backing Sen. Mitch McConnell's (R-Ky.) reelection fight, and American Crossroads, affiliated with the Karl-Rove-backed Crossroads GPS, both had far more male donors than female, according to available data.
One outside group, EMILY's List, counts more women than men among its contributors — in large part because of its focus on electing pro-choice female candidates.
And the Ready for Hillary super-PAC could be a reflection of that same trend. Clinton, if she runs for president in 2016, is expected to inspire unprecedented excitement among female voters looking to support what would be an historic first female president.
Former Rep. Ellen Tauscher, an adviser to Ready for Hillary, said in a statement that the high level of female donors reflects the historic potential of a Clinton run.
"Women are the majority of active voters in the country. Women know that for perhaps the first time in our history the most qualified and experienced person to run for president is also a woman, Hillary Clinton. Women also understand that politics is not a passive sport and that an active, grassroots campaign of millions of American women can be very influential in convincing Hillary Clinton that 2016 is the year to run for president," she said.