The debate caught the attention of Heidi Hartmann, president of the Institute for Women’s Policy Research. Hartmann, an economist who is not close to Yellen, said she has been repeatedly frustrated by a lack of women in the field. That concern was amplified by media coverage suggesting a Summers nomination was a done deal.

“I thought it was crowding her out of the marketplace,” Hartmann said. “I felt here was a supremely qualified woman who deserves a job. I sort of suspected that a lot of economists felt the same way.”

She said she searched feminist economic discussion groups online for a way to support Yellen but came up empty-handed. So she decided to start her own effort, enlisting help from Tyson and other prominent Yellen allies, including Blinder, former Obama economic adviser Christina Romer and Nobel laureate Joseph Stiglitz. Their letter to the White House went public with a dozen signatures in early September, the day after the Senate returned from recess. Two weeks later, it boasted 505 names .