DEBORAH SENN, the obvious choice to represent the people of Washington in the U.S. Senate with her proletarian avenger politics, came under attack recently from an unlikely source -- unions.

Late last month, leaders of the Washington Federation of State Employees (WFSE) Local 443 -- the union that represents workers in State Insurance Commissioner Deborah Senn's office -- fired off a letter to the union's endorsement council, opposing Senn's Democratic nomination for Slade Gorton's U.S. Senate seat.

"As Insurance Commissioner, Senn has a history of treating union members unfairly," wrote Local 443 President Allen Whitehead. "Her actions have been detrimental to labor's ability to organize..."

The problem isn't Senn's politics -- it's her personality. Three members of Senn's staff, who declined to give their names, accuse Senn of bad office management. Some have filed grievances against her, although they refused to show them to The Stranger. "She tends to shoot from the hip," says one bitter employee. "She is a very gruff person," adds another.

Senn isn't worried that the union's complaints will threaten her campaign. She dismisses the grievances, saying they were resolved.

By lefty, pro-consumer standards, Senn is a savior, especially for the poor and elderly. Since she was elected to the position in 1992, she has redefined her office. What was once a welcome mat for insurance companies is now a fairy godmother for consumers. Senn's office investigates about 10,000 consumer complaints a year. Senn also fights for reduced insurance costs and against limitations on coverage at every turn.

While it's hard to know whether the union grievances are merited without having seen them, Senn clearly rubs some the wrong way.

On Saturday, April 15, after the Washington State Labor Council voted with a 69.9 percent majority to endorse Senn, WFSE's Local 443 stormed out of the Georgetown Machinists Hall in protest.