The Municipal League of King County, a nonpartisan civic affairs group, issued its much-anticipated candidate ratings this morning, finding that state senator Ed Murray is the strongest candidate in the pack running for mayor of Seattle.

Murray, who comes to the race with a long track record of advancing same-sex marriage and passing budgets during the Democrats’ days controlling the legislature, earned the Muni League’s highest rating of “outstanding,” which the group designates for a candidate that brings “numerous outstanding contributions requiring skills related to the office, is a path-finding and respected leader, brings knowledge and creativity to issues facing the office.”

Murray is one notch above incumbent Mayor Mike McGinn, who earned a “very good” rating. The Muni League hands those out to a candidate that “makes significant contributions, is a skilled builder of consensus, inspires confidence in the way he/she would serve, is thorough and attentive to issues.” Former city council member Peter Steinbrueck also earned a “very good” rating.

Of the leading contenders, Bruce Harrell scored lowest. He earned only a “good.”

You can read the questionnaires here: Murray, McGinn, Steinbrueck, Harrell.

In other races, Council Member Sally Bagshaw (outstanding) bested challenger Sam Bellomio (not qualified), Council Member Mike O’Brien tied with challenger Albert Shen (both were very good), school board contender Suzanne Dale-Estey (outstanding) showed up liberal wiz Sue Peters (very good). Lots more races are rated here.

While the group is much respected, the Muni League remains opaque about its reasoning for the ratings, and for that reason—while ratings are one helpful metric for voters—the ranking should be taken with a grain of salt. For instance, they rate über-liberal O’Brien the same as business-fave Shen, even though the gulf of knowledge between them is obviously wide and deep. In our meetings, O’Brien was extremely familiar with all affairs facing city hall, while Shen was extremely spotty—and sometimes admittedly clueless—on city basics, such as steps needed to build light rail, a ballot measure on campaign finance reform, and bills authorizing homeless encampments, reforming panhandling laws, and permitting microhousing. The fact the Muni League measures those two equally makes me wonder if their ratings formula is one part logic and one part Magic 8 Ball.