In a sharp critique, Edwards said Clinton, U.S. senator from New York, isn't as vocal an advocate for women as she should be, the online magazine Salon reported Tuesday.

Edwards said she sympathized with the pressures Clinton faced in trying to make it in a man's world, saying she felt the same pressure when she practiced law.

"And sometimes you feel you have to behave as a man and not talk about women's issues," said Edwards, who also criticized Clinton for "not really talking about poverty," which often affects single mothers.

Her comments seemed intended to puncture Clinton's support among Democratic women. Salon said, polls suggest Clinton is influential with unmarried, blue-collar women, the same voters Edwards' husband, former U.S. Sen. John Edwards, D-N.C., is trying to sway.