BUFFALO, N.Y. – Former U.S. Attorney Denise O’Donnell entered the race for state attorney general yesterday with the endorsement of the Erie County Democratic Committee and a promise to “lead the fight for justice.”

Ms. O’Donnell is the only woman and the only upstate candidate in the race to succeed fellow Democrat Eliot Spitzer, who is running for governor.

“In every county and every community, people tell me that protecting New Yorkers is too important to be left to the politicians,” said Ms. O’Donnell, who has spent the last year gauging support.

President Clinton appointed Ms. O’- Donnell U.S. Attorney in the state’s Western District, covering Buffalo to Rochester, in 1998. She was asked to step down by the Bush administration in 2001 in the midst of what may have been her most high-profile case: the prosecution of James Kopp, the anti-abortion activist convicted of murdering abortion provider Dr. Barnett Slepian in 1998.

Since then, she has worked for Buffalo’s Hodgson Russ law firm.

As the state’s top prosecutor, Ms. O’Donnell said she would continue Mr. Spitzer’s anti-corruption efforts targeting Wall Street, while taking on additional initiatives such as identity theft.

“It’s an issue that impacts everyone from a consumer point of view, and something where I think we really need to stay ahead of the curve,” she said. “I’ve spent a lot of years prosecuting fraudulent schemes and computer crimes and feel that I have the expertise to make that issue a priority.”

Ms. O’Donnell’s husband, John, is an elected state Supreme Court justice and her son, Jack, is a University at Buffalo law student who has worked for Senator Schumer and now works for Comptroller Alan Hevesi.

A Siena College poll in February found Andrew Cuomo and a former New York City public advocate, Mark Green, leading the pack of attorney general candidates with 19% and 17% support, respectively, among potential Democratic voters.