The Municipal League of King County is following the Seattle Times' lead in endorsing against the library levy:

OPPOSES City of Seattle’s Prop.1 : The Seattle Public Library Operations Levy - The Seattle Public Library is an esteemed institution, a critically important city service, and a valuable neighborhood asset. Library operations should be funded through the City of Seattle’s General Fund, not a string of levies. We are deeply concerned that approving this levy will result in a continued practice of reducing allocations from the general fund. The lack of a citizens’ oversight component further weakens this proposal by failing to provide a sufficient level of transparency to the public. The City of Seattle needs to provide sustainable funding for this vital public service.

Yeah, sure, whatever. In the best of all possible worlds we'd fully fund the library through the general fund. But that's not the world we're living in. Opinion leaders like the Times and the Muni League have already failed to protect our city and our state from the current tax limiting regime. In fact, in some cases they've been complicit in it. So until they start fighting to repeal I-747's arbitrary one percent limit on property tax revenue increases, they have zero credibility in arguing to reject levy lid lifts on something as flimsy as principle.