In DC it's all about Benghazi or the IRS, but in Portland, Oregon the first thing on the docket is weirdness, of course. A close second, however, would be the raging fluoride debate, which has sparked protests throughout the city. Completely peaceful, but underlining a unique divide in the already culturally diverse city, it's anyone's guess which way the water fluoridation debate will blow.

In the 1950s, after health authorities began fluoridating U.S. water supplies, they faced opposition from groups like the John Birch Society, which called it "an unconstitutional mass medication of the public."

Sixty years later, the fight over fluoridation has erupted in Portland, where the battle has drawn in the city's craft-beer brewers, organic-food purveyors and environmentalists. Even some of the city's famed indie-rock musicians are taking sides.

The debate has prompted something of an existential crisis in this self-consciously liberal city, which votes Tuesday on whether to overturn the city council's 2012 decision to fluoridate.

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