The issue of race has surfaced in the contest between the two top Democratic rivals for governor, roiling a contest that had until this week been relatively quiet.

Christine Gregoire (search), the front-runner, on Wednesday angrily accused her primary rival, Ron Sims (search), of instigating an outcry over her membership in an all-white college sorority in the late-1960s. Sims, who is black, denies the accusation.

Gregoire, the state's first female attorney general, hit back Wednesday during a speech before the state Labor Council convention. "Knock it off, Ron!" Gregoire shouted, her voice shaking with anger. "It's time for this to stop."

Gregoire told the audience she has spent a lifetime fighting discrimination — and that Sims knows the truth. "He knows it is preposterous to suggest that I am in any way, shape or form a racist," she said.

Sims, the King County executive, addressed the same convention Wednesday, but made no reference to the sorority flap. He told reporters that neither he nor his campaign had anything to do with the matter.

He later issued a statement distancing himself from the brewing controversy. "Is Christine Gregoire a racist? Of course not," he said. "Have I ever inferred that she is? Absolutely not."

The issue arose on Monday when The Seattle Times wrote about Gregoire's time in the Kappa Delta sorority at the University of Washington and her decision to work from within the group to oppose its discriminatory membership rule.

She took little action during her time as a sister — even though as chapter president in 1969 she had to inform new recruits of the rule. But in 1973, as an alumna adviser, she spoke out against the policy during the sorority's national convention. Eventually, the rule was abolished.

Local black leaders spoke out after the story appeared, saying Gregoire's actions had no impact on changing the sorority's exclusionary rules, which violated the university's nondiscriminatory policies of the time. They also criticized Gregoire for not being repentant about her involvement in the sorority.

In his statement, Sims asked of Gregoire: "Is she proud of her role as a leader of the Kappa Delta sorority? She says she is. She says she was a leader to end discrimination. Was she or wasn't she? I think that's the real question at issue here.

"It has nothing to do with race. It has everything to do with whether she's taking credit for something she didn't do. It's not an issue of race, it's an issue of integrity."

Gregoire said the issue was dirty politics and deeply hurtful. She said the Sims camp helped publicize her membership in Kappa Delta, and likened Sims and his backers to former Swift boat gunners who have tried to undermine presidential nominee John Kerry.

The Times later said that neither Sims nor his campaign was the source for the newspaper's original story on the sorority. One of the Times editors was a sorority sister of Gregoire's, said political editor Tom Boyer.

Gregoire is widely expected to defeat Sims in the Sept. 14 Democratic primary and leads him 3-to-1 in fund raising. Gov. Gary Locke, who backs Gregoire but hasn't formally endorsed her, is retiring after two terms. Former state Sen. Dino Rossi is heavily favored to win the Republican primary.